Localization of opiate receptors in substantia nigra evidence by lesion studies.

From the effects of selective lesions it is concluded that opiate receptors are located on dopamine (DA) cell-bodies and/or dendrites as well as on GABA nerve-terminals in substantia nigra.

Self-association of synexin in the presence of calcium. Correlation with synexin-induced membrane fusion and examination of the structure of synexin aggregates.

It has been proposed (Creutz, C. E., Pazoles, C.

Role of anions in parathyroid hormone release from dispersed bovine parathyroid cells.

It is known that permeant anions are required for the release of epinephrine from isolated chromaffin granules and of serotonin from intact platelets. We have now investigated the role of anions in the release of a polypeptide hormone, parathyroid hormone, from dispersed bovine parathyroid cells. The release is inhibited 60%-80% by decreasing either [Cl-] or [OH-] and 60%-70% by replacement of NaCl with the impermeant anion isethionate.

Dopamine-beta-hydroxylase-induced changes in the electrical conductance of bimolecular lipid membranes.

Dopamine-beta-hydroxylase (DBH), an enzyme that catalyzes the conversion of dopamine (DA) to norepinephrine (NE) in adrenal medullary chromaffin granules, increases the electrical conductance of bimolecular lipid membranes. The conductances increase requires both DA and Ca2+ and occurs in discrete steps. The conductance, which increases as the square of the DBH concentration, is nonselective for cations over anions and requires the native conformation of DBH.

Evidence for control of serotonin secretion from human platelets by hydroxyl ion transport and osmotic lysis.

Serotonin secretion from human platelets, stimulated either by thrombin or the calcium ionophore A23187, was found to be inhibited by anion transport blocking drugs such as 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid (SITS), pyridoxal phosphate, probenecid, and suramin. These drugs have previously been shown to inhibit ATP-evoked release of epinephrine from isolated chromaffin granules by blocking chloride uptake and subsequent osmotic lysis. However, in contrast to granule release, platelet secretion was insensitive to chloride and, instead, was dependent on OH-.