The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
David L Hill - One of the best experts on this subject based on the ideXlab platform.
-
Neural plasticity in the Gustatory System.
Nutrition reviews, 2020Co-Authors: David L HillAbstract:Sensory Systems adapt to changing environmental influences by coordinated alterations in structure and function. These alterations are referred to as plastic changes. The Gustatory System displays numerous plastic changes even in receptor cells. This review focuses on the plasticity of Gustatory structures through the first synaptic relay in the brain. Unlike other sensory Systems, there is a remarkable amount of environmentally induced changes in these peripheral-most neural structures. The most consistent and largest changes occur to stimuli that also impact on homeostatic Systems, especially when the environmental manipulation is instituted during early development.
-
chorda tympani nerve terminal field maturation and maintenance is severely altered following changes to Gustatory nerve input to the nucleus of the solitary tract
The Journal of Neuroscience, 2011Co-Authors: Sara L Corson, David L HillAbstract:Neural competition among multiple inputs can affect the refinement and maintenance of terminal fields in sensory Systems. In the rat Gustatory System, the chorda tympani, greater superficial petrosal, and glossopharyngeal nerves have distinct but overlapping terminal fields in the first central relay, the nucleus of the solitary tract. This overlap is largest at early postnatal ages followed by a significant refinement and pruning of the fields over a 3 week period, suggesting that competitive mechanisms underlie the pruning. Here, we manipulated the putative competitive interactions among the three nerves by sectioning the greater superficial petrosal and glossopharyngeal nerves at postnatal day 15 (P15), P25, or at adulthood, while leaving the chorda tympani nerve intact. The terminal field of the chorda tympani nerve was assessed 35 d following nerve sections, a period before the sectioned nerves functionally regenerated. Regardless of the age when the nerves were cut, the chorda tympani nerve terminal field expanded to a volume four times larger than sham controls. Terminal field density measurements revealed that the expanded terminal field was similar to P15 control rats. Thus, it appears that the chorda tympani nerve terminal field defaults to its early postnatal field size and shape when the nerves with overlapping fields are cut, and this anatomical plasticity is retained into adulthood. These findings not only demonstrate the dramatic and lifelong plasticity in the central Gustatory System, but also suggest that corresponding changes in functional and taste-related behaviors will accompany injury-induced changes in brainstem circuits.
-
nerve target interactions in the Gustatory System following unilateral chorda tympani nerve section
Chemical Senses, 2005Co-Authors: David L HillAbstract:Although much effort has been directed at examining the morphological characteristics of denervated and regenerated taste buds, relatively little is known about the physiology of reinnervated taste cells (Vintschgau and Honigschmied, 1876; Guth, 1957; Fujimoto and Murray, 1970; Cheal and Oakley, 1977; Whitehead et al., 1987). Over 25 years ago, Oakley (Cheal et al., 1977) and colleagues found that some chorda tympani fibers reinnervated fungiform papillae on the gerbil’s anterior tongue in <2 weeks post-sectioning. Studies that examined recovery of taste function following nerve damage (Cain et al., 1996; Cheal et al., 1977; Ninomiya, 1998; Yasumatsu et al., 2003) indicate that regenerated taste nerves generally recover normal function after progressing through a transitional period. Only relatively recently has the impact of environment on the adult regenerating taste System been explored. Regenerating taste receptor cells in adult rats are susceptible to dietary influences (Hill and Phillips, 1994). Sectioning the chorda tympani unilaterally in rats fed a sodium-restricted diet at adulthood resulted in a regenerated nerve that had attenuated responses to sodium salts. Responses to other stimuli were unaffected. In addition, there were other, novel effects. In the same rat, the contralateral, uncut nerve was supersensitive to sodium salts. The supersensitivity developed progressively following an initial
-
neuron target plasticity in the peripheral Gustatory System
The Journal of Comparative Neurology, 2004Co-Authors: Marshall Hussain G Shuler, Robin F Krimm, David L HillAbstract:Taste bud volume on the anterior tongue in adult rats is matched by an appropriate number of innervating geniculate ganglion cells. The larger the taste bud, the more geniculate ganglion cells that innervate it. To determine if such a match is perturbed in the regenerated Gustatory System under different dietary conditions, taste bud volumes and numbers of innervating neurons were quantified in adult rats after unilateral axotomy of the chorda tympani nerve and/or maintenance on a sodium-restricted diet. The relationship between taste bud size and innervation was eliminated in rats merely fed a sodium-restricted diet; individual taste bud volumes were smaller than predicted by the corresponding number of innervating neurons. Surprisingly, the relationship was disrupted in a similar way on the intact side of the tongue in unilaterally sectioned rats, with no diet-related differences. The mismatch in these groups was due to a decrease in average taste bud volumes and not to a change in numbers of innervating ganglion cells. In contrast, individual taste bud volumes were larger than predicted by the corresponding number of innervating neurons on the regenerated side of the tongue; again, with no diet-related differences. However, the primary variable responsible for disrupting the function on the regenerated side was an approximate 20% decrease in geniculate ganglion cells available to innervate taste buds. Therefore, the neuron/target match in the peripheral Gustatory System is susceptible to surgical and/or dietary manipulations that act through multiple mechanisms. This System is ideally suited to model sensory plasticity in adults.
-
Neuron/target plasticity in the peripheral Gustatory System
The Journal of Comparative Neurology, 2004Co-Authors: Marshall Hussain G Shuler, Robin F Krimm, David L HillAbstract:Taste bud volume on the anterior tongue in adult rats is matched by an appropriate number of innervating geniculate ganglion cells. The larger the taste bud, the more geniculate ganglion cells that innervate it. To determine if such a match is perturbed in the regenerated Gustatory System under different dietary conditions, taste bud volumes and numbers of innervating neurons were quantified in adult rats after unilateral axotomy of the chorda tympani nerve and/or maintenance on a sodium-restricted diet. The relationship between taste bud size and innervation was eliminated in rats merely fed a sodium-restricted diet; individual taste bud volumes were smaller than predicted by the corresponding number of innervating neurons. Surprisingly, the relationship was disrupted in a similar way on the intact side of the tongue in unilaterally sectioned rats, with no diet-related differences. The mismatch in these groups was due to a decrease in average taste bud volumes and not to a change in numbers of innervating ganglion cells. In contrast, individual taste bud volumes were larger than predicted by the corresponding number of innervating neurons on the regenerated side of the tongue; again, with no diet-related differences. However, the primary variable responsible for disrupting the function on the regenerated side was an approximate 20% decrease in geniculate ganglion cells available to innervate taste buds. Therefore, the neuron/target match in the peripheral Gustatory System is susceptible to surgical and/or dietary manipulations that act through multiple mechanisms. This System is ideally suited to model sensory plasticity in adults.
Charles S Zuker - One of the best experts on this subject based on the ideXlab platform.
-
the neural representation of taste quality at the periphery
Nature, 2015Co-Authors: Robert P J Barretto, Sarah Gillissmith, Jayaram Chandrashekar, David A Yarmolinsky, Mark J Schnitzer, Nicholas J P Ryba, Charles S ZukerAbstract:Using two-photon microendoscopy and genetically encoded calcium indicators the tuning properties of the first neural station of the Gustatory System are explored; results reveal that ganglion neurons are matched to specific taste receptor cells, supporting a labelled line model of information transfer in the taste System. Individual tastes (sweet, sour, bitter, salty and umami) are detected by dedicated taste receptor cells on the tongue and palate, but how these signals are encoded and transmitted to the relevant part of the central nervous System — the Gustatory cortex — is unknown. Using transgenic mice expressing a calcium indicator in neurons, Charles Zuker and colleagues characterize the tuning properties of ganglion neurons, the first neural station of the Gustatory System. Ganglion neurons respond specifically to certain tastes, supporting a 'labelled line' model of information transfer in the taste System. The mammalian taste System is responsible for sensing and responding to the five basic taste qualities: sweet, sour, bitter, salty and umami. Previously, we showed that each taste is detected by dedicated taste receptor cells (TRCs) on the tongue and palate epithelium1. To understand how TRCs transmit information to higher neural centres, we examined the tuning properties of large ensembles of neurons in the first neural station of the Gustatory System. Here, we generated and characterized a collection of transgenic mice expressing a genetically encoded calcium indicator2 in central and peripheral neurons, and used a gradient refractive index microendoscope3 combined with high-resolution two-photon microscopy to image taste responses from ganglion neurons buried deep at the base of the brain. Our results reveal fine selectivity in the taste preference of ganglion neurons; demonstrate a strong match between TRCs in the tongue and the principal neural afferents relaying taste information to the brain; and expose the highly specific transfer of taste information between taste cells and the central nervous System.
Bijal P. Trivedi - One of the best experts on this subject based on the ideXlab platform.
-
Gustatory System: The finer points of taste
Nature, 2012Co-Authors: Bijal P. TrivediAbstract:As more receptors are defined, researchers will further unlock the mechanics of taste. How the mind perceives these sensory signals is another matter.
Robin F Krimm - One of the best experts on this subject based on the ideXlab platform.
-
neuron target plasticity in the peripheral Gustatory System
The Journal of Comparative Neurology, 2004Co-Authors: Marshall Hussain G Shuler, Robin F Krimm, David L HillAbstract:Taste bud volume on the anterior tongue in adult rats is matched by an appropriate number of innervating geniculate ganglion cells. The larger the taste bud, the more geniculate ganglion cells that innervate it. To determine if such a match is perturbed in the regenerated Gustatory System under different dietary conditions, taste bud volumes and numbers of innervating neurons were quantified in adult rats after unilateral axotomy of the chorda tympani nerve and/or maintenance on a sodium-restricted diet. The relationship between taste bud size and innervation was eliminated in rats merely fed a sodium-restricted diet; individual taste bud volumes were smaller than predicted by the corresponding number of innervating neurons. Surprisingly, the relationship was disrupted in a similar way on the intact side of the tongue in unilaterally sectioned rats, with no diet-related differences. The mismatch in these groups was due to a decrease in average taste bud volumes and not to a change in numbers of innervating ganglion cells. In contrast, individual taste bud volumes were larger than predicted by the corresponding number of innervating neurons on the regenerated side of the tongue; again, with no diet-related differences. However, the primary variable responsible for disrupting the function on the regenerated side was an approximate 20% decrease in geniculate ganglion cells available to innervate taste buds. Therefore, the neuron/target match in the peripheral Gustatory System is susceptible to surgical and/or dietary manipulations that act through multiple mechanisms. This System is ideally suited to model sensory plasticity in adults.
-
Neuron/target plasticity in the peripheral Gustatory System
The Journal of Comparative Neurology, 2004Co-Authors: Marshall Hussain G Shuler, Robin F Krimm, David L HillAbstract:Taste bud volume on the anterior tongue in adult rats is matched by an appropriate number of innervating geniculate ganglion cells. The larger the taste bud, the more geniculate ganglion cells that innervate it. To determine if such a match is perturbed in the regenerated Gustatory System under different dietary conditions, taste bud volumes and numbers of innervating neurons were quantified in adult rats after unilateral axotomy of the chorda tympani nerve and/or maintenance on a sodium-restricted diet. The relationship between taste bud size and innervation was eliminated in rats merely fed a sodium-restricted diet; individual taste bud volumes were smaller than predicted by the corresponding number of innervating neurons. Surprisingly, the relationship was disrupted in a similar way on the intact side of the tongue in unilaterally sectioned rats, with no diet-related differences. The mismatch in these groups was due to a decrease in average taste bud volumes and not to a change in numbers of innervating ganglion cells. In contrast, individual taste bud volumes were larger than predicted by the corresponding number of innervating neurons on the regenerated side of the tongue; again, with no diet-related differences. However, the primary variable responsible for disrupting the function on the regenerated side was an approximate 20% decrease in geniculate ganglion cells available to innervate taste buds. Therefore, the neuron/target match in the peripheral Gustatory System is susceptible to surgical and/or dietary manipulations that act through multiple mechanisms. This System is ideally suited to model sensory plasticity in adults.
-
early dietary sodium restriction disrupts the peripheral anatomical development of the Gustatory System
Journal of Neurobiology, 1999Co-Authors: Robin F Krimm, David L HillAbstract:Dietary sodium restriction has profound effects on the development of peripheral taste function and central taste System anatomy. This study examined whether early dietary sodium restriction also affects innervation of taste buds. The number of geniculate ganglion cells that innervate single fungiform taste buds were quantified for the midregion of the tongue in two groups of rats: those fed either a low-sodium diet and those fed a sodium replete diet (control rats) from early prenatal development through adulthood. The same mean number of ganglion cells in developmentally sodium-restricted and control adult rats innervated taste buds on the midregion of the tongue. However, the characteristic relationship of the larger the taste bud, the more neurons that innervate it did not develop in sodium-restricted rats. The failure to form such a relationship in experimental rats was likely due to a substantially smaller mean taste bud volume than controls and probably not to changes in innervation. Further experiments demonstrated that the altered association between number of innervating neurons and taste bud size in restricted rats was reversible. Feeding developmentally sodium-restricted rats a sodium replete diet at adulthood resulted in an increase in taste bud size. Accordingly, the high correlation between taste bud volume and innervation was established in sodium-replete rats. Findings from the current study reveal that early dietary manipulations influence neuron–target interactions; however, the effects of dietary sodium restriction on peripheral Gustatory anatomy can be completely restored, even in adult animals. © 1999 John Wiley & Sons, Inc. J Neurobiol 39: 218–226, 1999
Marshall Hussain G Shuler - One of the best experts on this subject based on the ideXlab platform.
-
neuron target plasticity in the peripheral Gustatory System
The Journal of Comparative Neurology, 2004Co-Authors: Marshall Hussain G Shuler, Robin F Krimm, David L HillAbstract:Taste bud volume on the anterior tongue in adult rats is matched by an appropriate number of innervating geniculate ganglion cells. The larger the taste bud, the more geniculate ganglion cells that innervate it. To determine if such a match is perturbed in the regenerated Gustatory System under different dietary conditions, taste bud volumes and numbers of innervating neurons were quantified in adult rats after unilateral axotomy of the chorda tympani nerve and/or maintenance on a sodium-restricted diet. The relationship between taste bud size and innervation was eliminated in rats merely fed a sodium-restricted diet; individual taste bud volumes were smaller than predicted by the corresponding number of innervating neurons. Surprisingly, the relationship was disrupted in a similar way on the intact side of the tongue in unilaterally sectioned rats, with no diet-related differences. The mismatch in these groups was due to a decrease in average taste bud volumes and not to a change in numbers of innervating ganglion cells. In contrast, individual taste bud volumes were larger than predicted by the corresponding number of innervating neurons on the regenerated side of the tongue; again, with no diet-related differences. However, the primary variable responsible for disrupting the function on the regenerated side was an approximate 20% decrease in geniculate ganglion cells available to innervate taste buds. Therefore, the neuron/target match in the peripheral Gustatory System is susceptible to surgical and/or dietary manipulations that act through multiple mechanisms. This System is ideally suited to model sensory plasticity in adults.
-
Neuron/target plasticity in the peripheral Gustatory System
The Journal of Comparative Neurology, 2004Co-Authors: Marshall Hussain G Shuler, Robin F Krimm, David L HillAbstract:Taste bud volume on the anterior tongue in adult rats is matched by an appropriate number of innervating geniculate ganglion cells. The larger the taste bud, the more geniculate ganglion cells that innervate it. To determine if such a match is perturbed in the regenerated Gustatory System under different dietary conditions, taste bud volumes and numbers of innervating neurons were quantified in adult rats after unilateral axotomy of the chorda tympani nerve and/or maintenance on a sodium-restricted diet. The relationship between taste bud size and innervation was eliminated in rats merely fed a sodium-restricted diet; individual taste bud volumes were smaller than predicted by the corresponding number of innervating neurons. Surprisingly, the relationship was disrupted in a similar way on the intact side of the tongue in unilaterally sectioned rats, with no diet-related differences. The mismatch in these groups was due to a decrease in average taste bud volumes and not to a change in numbers of innervating ganglion cells. In contrast, individual taste bud volumes were larger than predicted by the corresponding number of innervating neurons on the regenerated side of the tongue; again, with no diet-related differences. However, the primary variable responsible for disrupting the function on the regenerated side was an approximate 20% decrease in geniculate ganglion cells available to innervate taste buds. Therefore, the neuron/target match in the peripheral Gustatory System is susceptible to surgical and/or dietary manipulations that act through multiple mechanisms. This System is ideally suited to model sensory plasticity in adults.