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Per Södersten - One of the best experts on this subject based on the ideXlab platform.

  • Cholecystokinin Octapeptide inhibits carbohydrate but not protein intake
    American Journal of Physiology-regulatory Integrative and Comparative Physiology, 1997
    Co-Authors: A H Mamoun, J Bergstrom, Per Södersten
    Abstract:

    Male rats ingested about half as much of an intraorally infused (1 ml/min) carbohydrate solution compared with a protein solution. Blood levels of Cholecystokinin Octapeptide (CCK-8) had increased to 13.6 +/- 1.4 and 16.7 +/- 1.7 pmol/l when the rats stopped ingesting carbohydrate or protein and continued to increase to 35.6 +/- 3.2 pmol/l 30 min after the carbohydrate meal and 34.4 +/- 3.5 pmol/l 60 min after the protein meal. Intraperitoneal injection of CCK-8 (0.6-5.0 micrograms) inhibited and injection of the CCKA-receptor antagonist L-364, 718 (20-80 micrograms) facilitated carbohydrate intake, but neither CCK-8 nor L-364,718 affected protein intake. The results suggest that CCK-8 is not involved in regulating the duration of a protein meal but may be involved in regulating carbohydrate intake. The postprandial period of suppression of protein intake correlated with the disappearance of some amino acids, e.g., Arg, Tyr, and Trp, in the blood, and this may be of importance for protein ingestion, since these amino acids are neurotransmitter precursors.

  • A Comparison Between the Effect of Cholecystokinin Octapeptide and Apomorphine on Ingestion of Intraorally Administered Sucrose in Male Rats
    Journal of Neuroendocrinology, 1992
    Co-Authors: I. Bednar, G. A. Qureshi, Per Södersten
    Abstract:

    The involvement of dopamine receptors in the inhibitory effect of Cholecystokinin Octapeptide on ingestive behaviour was investigated. Male rats were infused intraorally with a 1 M solution of sucrose and the amount ingested after treatment with the dopamine receptor agonist apomorphine was compared with that after treatment with Cholecystokinin Octapeptide. The test allows a distinction between the consummatory aspects of ingestive behaviour, i.e. responses used to ingest food, from the appetitive aspects, i.e. responses used to obtain food, because it ignores the latter aspects. Comparisons were also made between the effects of apomorphine and Cholecystokinin Octapeptide on pellet intake, a test in which the rat has to display appetitive ingestive behaviour. Injection of apomorphine (400 μg) increased the concentration of plasma apomorphine within 0.3 min and the concentration of dopamine in the cerebrospinal fluid within 1 min of injection and induced behavioural stereotypes within 10 min in food-deprived male rats. Plasma apomorphine and cerebrospinal fluid dopamine levels had decreased by 30 min and the behavioural stereotypies had decreased by 40 min after the injection. Injection of apomorphine also inhibited the consumption of food pellets and the ingestion of sucrose. Inhibition of pellet and sucrose ingestion paralleled the effect of apomorphine on Stereotypie behaviour. Thus, injection of a dopamine receptor agonist is followed by alterations in plasma levels of the agonist, cerebrospinal fluid dopamine levels and in Stereotypie and ingestive behaviour which occur in parallel, in an inverted U-shaped manner and with a temporal delay between each event. These results show a close correlation between dopamine receptor stimulation and inhibition of ingestive behaviour. However, reversal of the inhibitory effect of apomorphine on ingestive behaviour required pretreatment with a lower dose of a dopamine receptor antagonist (cis-flupentixol) (0.1 mg) than reversal of Stereotypie behaviour (0.8 mg). The effect of dopamine receptor stimulation on consummatory ingestive behaviour is thus relatively weak and not secondary to the induction of Stereotypic behaviour. Treatment with a high dose of cis-flupentixol (0.8 mg) caused a prolonged period of immobility but had no effect on the ingestion of sucrose. Dopamine receptor blockade, therefore, interferes with appetitive, but not consummatory ingestive behaviour. Injection of Cholecystokinin Octapeptide (5 μg) suppressed pellet and sucrose intake in a manner comparable to that of apomorphine, but induced no behavioural stereotypes and caused a gradual, rather than inverted U-shaped, increase in the concentration of dopamine in the cerebrospinal fluid that did not correlate with the effect on ingestive behaviour. Furthermore, while the inhibitory effect of apomorphine on the ingestion of sucrose was reversed by pretreatment with a low dose of cis-flupentixol (0.1 mg), the inhibitory effect of Cholecystokinin Octapeptide was only partially reversed by cis-flupentixol and a higher dose (0.8 mg) was required. Blockade of Cholecystokinin-A receptors, by treatment with L-364,718, but not Cholecystokinin-B receptors, by treatment with L-365,260, blocked the inhibitory effect of Cholecystokinin Octapeptide and, by itself, L-364,718 increased the amount of ingested sucrose. The inhibitory effect of Cholecystokinin Octapeptide on consummatory ingestive behaviour, which is mediated by Cholecystokinin-A receptors, is likely to involve mechanisms in addition to dopaminergic ones.

  • Evidence that Release of Dopamine in the Brain is Involved in the Inhibitory Effect of Cholecystokinin Octapeptide on Ingestion of Intraorally Administered Sucrose in Male Rats
    Journal of Neuroendocrinology, 1992
    Co-Authors: I. Bednar, G. A. Qureshi, Per Södersten
    Abstract:

    To study the possibility that release of dopamine in the brain mediates the inhibitory effect of Cholecystokinin Octapeptide on ingestive behaviour, the effect of amphetamine on intake of pellets or an intraorally administered sucrose solution was compared with that of Cholecystokinin Octapeptide. Additionally, comparisons were made between the effect of Cholecystokinin Octapeptide and pargyline, a monoamine oxidase inhibitor, and α-methyl-ρ-tyrosine, a tyrosine hydroxylase inhibitor. While amphetamine dose-dependently inhibited pellet intake it failed to inhibit sucrose intake in doses which caused behavioural stereotypies (

  • Involvement of dopamine in inhibition of food intake by Cholecystokinin Octapeptide in male rats.
    Journal of Neuroendocrinology, 1991
    Co-Authors: I. Bednar, G. Forsberg, A. Lindén, G. A. Qureshi, Per Södersten
    Abstract:

    Deprivation of food reduced the level of dopamine in the cerebrospinal fluid of male rats and subsequent ingestion of food or intraperitoneal injection of Cholecystokinin Octapeptide restored the level. Injection of a dopamine receptor agonist (apomorphine) or Cholecystokinin Octapeptide inhibited food intake and these effects were reversed by pretreatment with a dopamine receptor antagonist (cis-flupentixol). Blockade of Cholecystokinin-A receptors, by treatment with L-364,718, but not Cholecystokinin-B receptors, by treatment with L-365,260, blocked the inhibitory effect of Cholecystokinin Octapeptide on food intake but did not affect the inhibitory effect of apomorphine. It is suggested that Cholecystokinin interacts with dopamine in the control of food intake.

Gyula Telegdy - One of the best experts on this subject based on the ideXlab platform.

Eva Biro - One of the best experts on this subject based on the ideXlab platform.

Edward Karpinski - One of the best experts on this subject based on the ideXlab platform.

I. Bednar - One of the best experts on this subject based on the ideXlab platform.

  • A Comparison Between the Effect of Cholecystokinin Octapeptide and Apomorphine on Ingestion of Intraorally Administered Sucrose in Male Rats
    Journal of Neuroendocrinology, 1992
    Co-Authors: I. Bednar, G. A. Qureshi, Per Södersten
    Abstract:

    The involvement of dopamine receptors in the inhibitory effect of Cholecystokinin Octapeptide on ingestive behaviour was investigated. Male rats were infused intraorally with a 1 M solution of sucrose and the amount ingested after treatment with the dopamine receptor agonist apomorphine was compared with that after treatment with Cholecystokinin Octapeptide. The test allows a distinction between the consummatory aspects of ingestive behaviour, i.e. responses used to ingest food, from the appetitive aspects, i.e. responses used to obtain food, because it ignores the latter aspects. Comparisons were also made between the effects of apomorphine and Cholecystokinin Octapeptide on pellet intake, a test in which the rat has to display appetitive ingestive behaviour. Injection of apomorphine (400 μg) increased the concentration of plasma apomorphine within 0.3 min and the concentration of dopamine in the cerebrospinal fluid within 1 min of injection and induced behavioural stereotypes within 10 min in food-deprived male rats. Plasma apomorphine and cerebrospinal fluid dopamine levels had decreased by 30 min and the behavioural stereotypies had decreased by 40 min after the injection. Injection of apomorphine also inhibited the consumption of food pellets and the ingestion of sucrose. Inhibition of pellet and sucrose ingestion paralleled the effect of apomorphine on Stereotypie behaviour. Thus, injection of a dopamine receptor agonist is followed by alterations in plasma levels of the agonist, cerebrospinal fluid dopamine levels and in Stereotypie and ingestive behaviour which occur in parallel, in an inverted U-shaped manner and with a temporal delay between each event. These results show a close correlation between dopamine receptor stimulation and inhibition of ingestive behaviour. However, reversal of the inhibitory effect of apomorphine on ingestive behaviour required pretreatment with a lower dose of a dopamine receptor antagonist (cis-flupentixol) (0.1 mg) than reversal of Stereotypie behaviour (0.8 mg). The effect of dopamine receptor stimulation on consummatory ingestive behaviour is thus relatively weak and not secondary to the induction of Stereotypic behaviour. Treatment with a high dose of cis-flupentixol (0.8 mg) caused a prolonged period of immobility but had no effect on the ingestion of sucrose. Dopamine receptor blockade, therefore, interferes with appetitive, but not consummatory ingestive behaviour. Injection of Cholecystokinin Octapeptide (5 μg) suppressed pellet and sucrose intake in a manner comparable to that of apomorphine, but induced no behavioural stereotypes and caused a gradual, rather than inverted U-shaped, increase in the concentration of dopamine in the cerebrospinal fluid that did not correlate with the effect on ingestive behaviour. Furthermore, while the inhibitory effect of apomorphine on the ingestion of sucrose was reversed by pretreatment with a low dose of cis-flupentixol (0.1 mg), the inhibitory effect of Cholecystokinin Octapeptide was only partially reversed by cis-flupentixol and a higher dose (0.8 mg) was required. Blockade of Cholecystokinin-A receptors, by treatment with L-364,718, but not Cholecystokinin-B receptors, by treatment with L-365,260, blocked the inhibitory effect of Cholecystokinin Octapeptide and, by itself, L-364,718 increased the amount of ingested sucrose. The inhibitory effect of Cholecystokinin Octapeptide on consummatory ingestive behaviour, which is mediated by Cholecystokinin-A receptors, is likely to involve mechanisms in addition to dopaminergic ones.

  • Evidence that Release of Dopamine in the Brain is Involved in the Inhibitory Effect of Cholecystokinin Octapeptide on Ingestion of Intraorally Administered Sucrose in Male Rats
    Journal of Neuroendocrinology, 1992
    Co-Authors: I. Bednar, G. A. Qureshi, Per Södersten
    Abstract:

    To study the possibility that release of dopamine in the brain mediates the inhibitory effect of Cholecystokinin Octapeptide on ingestive behaviour, the effect of amphetamine on intake of pellets or an intraorally administered sucrose solution was compared with that of Cholecystokinin Octapeptide. Additionally, comparisons were made between the effect of Cholecystokinin Octapeptide and pargyline, a monoamine oxidase inhibitor, and α-methyl-ρ-tyrosine, a tyrosine hydroxylase inhibitor. While amphetamine dose-dependently inhibited pellet intake it failed to inhibit sucrose intake in doses which caused behavioural stereotypies (

  • Involvement of dopamine in inhibition of food intake by Cholecystokinin Octapeptide in male rats.
    Journal of Neuroendocrinology, 1991
    Co-Authors: I. Bednar, G. Forsberg, A. Lindén, G. A. Qureshi, Per Södersten
    Abstract:

    Deprivation of food reduced the level of dopamine in the cerebrospinal fluid of male rats and subsequent ingestion of food or intraperitoneal injection of Cholecystokinin Octapeptide restored the level. Injection of a dopamine receptor agonist (apomorphine) or Cholecystokinin Octapeptide inhibited food intake and these effects were reversed by pretreatment with a dopamine receptor antagonist (cis-flupentixol). Blockade of Cholecystokinin-A receptors, by treatment with L-364,718, but not Cholecystokinin-B receptors, by treatment with L-365,260, blocked the inhibitory effect of Cholecystokinin Octapeptide on food intake but did not affect the inhibitory effect of apomorphine. It is suggested that Cholecystokinin interacts with dopamine in the control of food intake.