Almegård B, Bill A
Department of Physiology and Medical Biophysics, Uppsala University, Sweden.
Eur J Pharmacol. 1993 Nov 30;250(1):31-5. doi: 10.1016/0014-2999(93)90617-q.
The miotic effects of C-terminal calcitonin gene-related peptide (CGRP) fragments, somatostatin-28 and vasopressin have been evaluated with special attention being paid to possible interactions with cholecystokinin (CCK)A receptors. The peptides were injected intracamerally to anesthetized monkeys pretreated with indomethacin and atropine. CGRP-(32-37) induced a miosis with a potency 1000 times lower than that previously found with sulphated CCK-8. Two other fragments, CGRP-(30-37) and CGRP-(31-37), also had miotic properties. The CGRP-(32-37)-induced miosis was antagonized by the CCKA receptor antagonist loxiglumide. No contractile effect was elicited by 67 pmol-7.4 nmol somatostatin-28. Vasopressin (360 pmol) caused a small reduction in pupil size. Loxiglumide pretreatment did not affect the reduction in pupil size but a vasopressin receptor antagonist partly inhibited the response. The results indicate that CGRP-(32-37) is a miotic with low potency but high efficacy in the monkey eye, probably interacting with CCKA receptors, and that vasopressin is a mitotic with low potency and efficacy, probably acting via vasopressin receptors.
已对降钙素基因相关肽（CGRP）C末端片段、生长抑素-28和血管加压素的缩瞳作用进行了评估，特别关注了它们与胆囊收缩素（CCK）A受体可能存在的相互作用。将这些肽经前房内注射到用吲哚美辛和阿托品预处理过的麻醉猴体内。CGRP-（32 - 37）诱导的缩瞳效力比先前发现的硫酸化CCK-8低1000倍。另外两个片段CGRP-（30 - 37）和CGRP-（31 - 37）也具有缩瞳特性。CCKA受体拮抗剂洛西格列姆可拮抗CGRP-（32 - 37）诱导的缩瞳。67 pmol - 7.4 nmol的生长抑素-28未引起收缩效应。血管加压素（360 pmol）使瞳孔大小略有减小。预先使用洛西格列姆不影响瞳孔大小的减小，但血管加压素受体拮抗剂可部分抑制该反应。结果表明，CGRP-（32 - 37）在猴眼中是一种效力低但效能高的缩瞳剂，可能与CCKA受体相互作用，而血管加压素是一种效力和效能均低的缩瞳剂，可能通过血管加压素受体起作用。
