title: Comparative studies with linear and cyclic somatostatin on the self-stimulation of rats.
abstract: In the present study the dose-related effects of linear and cyclic somatostatin were compared on the self-stimulation rate of rats. Twenty micrograms of linear somatostatin administered intracerebroventricularly (icv.) markedly decreased the self-stimulation rate, while 5 micrograms and 10 micrograms was ineffective. Cyclic somatostatin in a dose of 1 microgram caused a transitory but not significant increase in the self-stimulation rate, which later returned to the control level. Five micrograms and 10 micrograms of the peptide decreased the self-stimulation rate. These results indicate that the cyclic somatostatin is more effective in inhibiting the self-stimulation rate than the linear one.
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012653:Self Stimulation / Q000187:drug effects*; D013004:Somatostatin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology*
chemical_list: D013004:Somatostatin