The effects of diltiazem onPeriplaneta americana

Summary The effects of the calcium antagonist diltiazem on nerve and muscle in the cockroachPeriplaneta americana were examined. Diltiazem was observed to inhibit myogenic and glutamate-induced contractions of the visceral muscle while having either a potentiating, an inhibiting or a biphasic effect against proctolin-induced contractions. Against the isolated nervous system, diltiazem induced an increase in spontaneous discharge activity, followed by nerve block. Injection of diltiazem into cockroaches produced behavioral and toxic effects.Acknowledgments. The expert technical assistance of Miss Susan Auffarth is gratefully acknowledged. Bioresmethrin was provided by Dr. G.J.P. Singh. We would like to thank Nordic Laboratories for the gift of diltiazem.     

Development of the new Pacinian corpuscles. Studies on the foreign innervation of mesentery

Zusammenfassung Nach Implantation des proximalen Stumpfes eines afferenten, somatosensiblen Nerven in das Mesenterium einer Katze bilden sich um die auswachsenden Nervenfasern nach 3–5 Monaten neue, aber dem Ort entsprechende Rezeptoren aus, im Fall des Katzenmesenteriums also Pacinische Körperchen, Rezeptoren, die normalerweise nicht im Gebiet des implantierten Nerven vorkommen.     

Molecular forms of dopamine beta-hydroxylase in rat superior cervical ganglion and adrenal gland

Summary Dopamine beta-hydroxylase (DBH) enzyme activity was associated in rat superior cervical ganglion with tetrameric DBH-A (294,000 D) and dimeric DBH-B (147,000 D) and in rat adrenal gland with DBH-A and a novel molecular form of DBH, defined as DBH-C, with a molecular weight of 125,000 D. Pretreatment of the rats with cycloheximide markedly reduced DBH activity without altering the molecular heterogeneity.