W. Lewis Collier

Learn More
The presence of 5-hydroxytryptamine (5-HT)-like immunoreactivity (IR) was studied in the rat female reproductive system using polyclonal antibodies directed against 5-HT. Moreover, 5-HT levels in the ovary, oviduct, uterus, and cervix were measured by high-pressure liquid chromatography with electrochemical detection. The highest 5-HT concentrations were(More)
The anatomical localization of gamma-aminobutyric acid type A (GABA-A) receptor sites in the rat superior cervical ganglion was studied using combined radioreceptor binding and autoradiographic techniques. 3H-Muscimol was used as a ligand of GABA-A receptor sites. The binding was consistent with the labelling of GABA-A sites. The dissociation constant value(More)
The effect of dopamine on 3'-5'-cyclic adenosine monophosphate (cAMP) generation in the rabbit superior mesenteric artery was studied in order to identify dopamine receptors. Dopamine added to homogenates of superior mesenteric artery increased the concentration of cAMP. The stimulation of cAMP levels elicited by dopamine was unaffected by alpha or(More)
By using combined in vitro radioreceptor binding and autoradiographic techniques, the pharmacological profile and the anatomical localization of dopamine-1 (DA-1) and dopamine-2 (DA-2) receptors were assessed in rat cerebral, mesenteric and renal arteries. 3H-SCH 23390 (DA-1 ligand) was bound by the medial layer of cerebral, mesenteric and renal arteries(More)
1. In vitro addition of dopamine (DA) or of DA-1 receptor agonists increases 3'- 5'-cyclic adenosine monophosphate (cAMP) levels through the stimulation of DA-1 receptors. 2. Although receptor binding studies suggest the existence of DA-2 receptors in the renal cortex, the presence of DA receptors negatively coupled to cAMP generation (DA-2 effect) has not(More)
Combined in vivo radioreceptor binding and autoradiographic techniques were used to characterized the pharmacological profile and to study the anatomical localization of dopamine (DA) DA-1 receptor sites in sections of rabbit pulmonary artery. [3H]R-(+)-8-chloro-2,3,4,5-tetrahydro-5-phenyl-1H-3-benzazepin-7- alhemimaleate (SCH 23390), which was used as a(More)
At first glance, it is satisfying to see the progress which has been made in the study of neurotransmitters. We have learned a great deal in the last number of years. First, we have been able to identify previously unknown compounds which affect the nervous system or associated peripheral organs. We now know a great deal about the metabolism of these(More)
Using mature (12 months), old (70 months) rabbits and 3H-labeled spiroperidol, the characteristics of renal artery dopamine receptors were studied. In old age the dissociation constant of [3H]spiroperidol was unchanged, while maximum specific binding was reduced more than 45%. The present data seem to indicate an impairment of peripheral dopaminergic(More)
The influence of aging on glutathione levels and distribution in the heart was studied in male Sprague-Dawley rats of 3 (young), 12 (adult) and 24 (old) months of age using biochemical and histofluorescence techniques, respectively. Biochemical assays of reduced glutathione (GSH) in the right and left ventricles and in the septum showed a significant(More)
The distribution of monoamine oxidase types A and B in the heart of young (3-month-old) and aged (26-month) Wistar rats was studied by histochemical methods. In young rats, MAO activity was higher in the left ventricle than in the right. Enzyme reactivity was present within both muscle cells and the blood vessel wall. Histochemical staining was abolished by(More)