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PubMed · 2991797

Calmodulin inhibitors decrease the CRF-and AVP-induced ACTH release in vitro: interaction of calcium-calmodulin and the cyclic AMP system.

K Murakami·K Hashimoto·Z Ota
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Abstract

The effect of N-(6-aminohexyl)-5-chloro-naphthalene-1-sulfomide (W-7) and trifluoperazine (TFP) was examined on ACTH release from cultured rat anterior pituitary cells and pituitary halves. These drugs significantly inhibited the ACTH release induced by synthetic ovine corticotropin-releasing factor (CRF) in a dose-related manner. In pituitary halves, arginine vasopressin (AVP) at 10 and 100 ng/ml showed almost the same ACTH-releasing activity as CRF at the same concentrations. W-7 and TFP inhibited the CRF-and AVP-induced ACTH release from pituitary halves. The cyclic AMP levels in the pituitary halves were significantly increased by CRF, but not AVP. Although W-7 inhibited CRF-induced ACTH release, it did not have an effect in cyclic AMP accumulation. These results suggest that CRF exerts ACTH-releasing activity through both the calcium-calmodulin system and cyclic AMP system and that AVP stimulates ACTH release mainly through the calcium-calmodulin system.

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Adrenocorticotropic HormoneAnimalsArginine VasopressinCalciumCalmodulinCells, CulturedCorticotropin-Releasing HormoneCyclic AMPMalePituitary Gland, AnteriorRatsRats, Inbred StrainsSulfonamidesTrifluoperazineJournal Article

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K Murakami, K Hashimoto, Z Ota. 1985. Calmodulin inhibitors decrease the CRF-and AVP-induced ACTH release in vitro: interaction of calcium-calmodulin and the cyclic AMP system.. https://doi.org/10.1159/000124146

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