Derivatives and Analogues of Cyclic Nucleotides

Calcium‐dependent stimulation of prolactin release in rat anterior pituitaryin vitro by n6‐monobutyryl adenosine 3′,5′‐monophosphate

“…Recent data indicate that cyclic AMP is also in volved in the action of the hypothalamic releasing hormones in the anterior pituitary gland [1][2][3][4][5][6][7][8][9][10][11][12][13][14][32][33][34][35][36][37][38][39]. It has in fact been found that hypothalamic extracts stimulate adenohypophyseal adenyl cyclase activity [32], that cyclic AMP-dependent protein kinase is widely distributed among subce~ular structures of the anterior pituitary gland [34][35][36], and that cyclic AMP stimulates both total protein synthesis [3,37] and the release of specific hormones by the adenohypophysis [1][2][3][4][5][6][7][8][9][10][11][12][13][14]38].…”

“…It is well accepted that adenosine 3',5'-monophosphate (cyclic AMP), or its derivatives, stimulate the release of growth hormone [1][2][3][4][5], thyrotropic hormone [6][7][8], adrenocorticotropic hormone [9,10], luteinizing hormone [11 ] and follicle-stimulating hormone [12]. However, no such evidence had yet been obtained for another anterior pituitary hormone, prolactin.…”

“…However, the recent demonstration of prolactin-releasing activity in extracts of median eminence [22,23] demonstrated for the 5 other anterior pituitary hormones [1][2][3][4][5][6][7][8][9][10][11][12].…”

Cyclic AMP and Cyclic GMP

“…The same derivatives and also 8-bromo-cAMP and 8-thio-cAMP increased more effectively than cAMP the release of GH, but not the release of prolactin. The effect of 8-thio-cAMP was considerably enhanced by dibutyrylation (65). Iso-cAMP, which is quite active on TSH release, was far less potent on GH release (72).…”

Steroidogenic and lipolytic activities of 8-substituted derivatives of cyclic 3',5'-adenosine monophosphate

“…1971 ;Posternak et al, 1971). Biological activities reported for the eight-substituted cAMP derivatives have included activation of cAMP-dependent protein kinase (Muneyama et al, 1971), activation of glycogen phosphorylase (Michal et al, 1970a) and release of anterior pituitary hormones (Posternak et al, 1971). The eight-substituted derivatives also have been shown to inhibit cyclic nucleotide phosphodiesterase (Muneyama et al, 1971; D. N. Harris and M.…”