Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01178 (oxytocin)
 15,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Incubation of pineal acetyl-CoA hydrolase preparations with disulfide peptides activates the enzyme. Activation of somatostatin, the most potent peptide tested, is enhanced at higher pH, indicating that disulfide exchange is probably involved. This interpretation is supported by the observation that activation is reversed by dithiothreitol treatment. The order of potency is somatostatin = [Tyr1]somatostatin greater than or equal to Tyr-somatostatin greater than vasopressin = pressinoic acid = [Arg8]vasotocin greater than oxytocin. Insulin, insulin A, insulin B, and [Asu1,6, Arg8]vasopressin were ineffective. This order of potency is distinctly different from that for the inactivation of pineal N-acetyltransferase (Namboodiri, M. A. A., Favilla, J., and Klein, D. C. (1981) Science 213, 571-573) by these peptides. Examination of the primary structure of the peptides reveals that the above order of potency is consistent with the predictions of the nearest neighbor model as applied to the disulfide group.
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PMID:Activation of pineal acetyl coenzyme A hydrolase by disulfide peptides. 612 7

In addition to the stimulating influence of the sympathetic system on the function of the mammalian pineal gland, neuropeptides such as neuropeptide Y, vasoactive intestinal polypeptide and arginine-vasopressin (AVP) are thought to function as modulators. Since AVP has been shown to influence pineal melatonin synthesis, the aim of the present study was to investigate the possible effects of the second hypothalamic nonapeptide oxytocin (OT), which likewise has been detected in the pineal gland. We therefore studied "synaptic" ribbon (SR) numbers, N-acetyltransferase (NAT) activity and the intracellular concentration of cyclic guanosine monophosphate (cGMP) following in vitro incubation of rat pineals in media containing OT (10(-5) M), noradrenaline (NA, 10(-5) M) or both NA and OT. Pineal glands were derived from rats of three different strains (Sprague-Dawley, Long-Evans and the AVP-deficient strain Brattleboro). Neither morphological nor biochemical analyses showed a difference between control and OT-incubated organs in any of the strains tested. In Brattleboro rats, but not in the other strains, noradrenaline slightly increased the number of SR which was not observed when NA and OT were combined. The addition of NA resulted in distinct augmentation of NAT activity and cGMP content, which were not affected by additional OT application. These results suggest that oxytocin is not crucially involved in the regulation of pineal gland function.
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PMID:Lack of effect of oxytocin on the numbers of "synaptic" ribbons, cyclic guanosine monophosphate and serotonin N-acetyltransferase activity in organ-cultured pineals of three strains of rats. 826 81