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Z Gottesfeld

Publications and source records attributed to Z Gottesfeld.

At least 37 records · Page 2Linked to original sources

Evidence for cholinergic muscarinic receptors on mediodorsal thalamic projections to the anterior cingulate cortex.

Cholinergic muscarinic receptor binding was analyzed in the rat brain anterior cingulate cortex following lesions of the mediodorsal or anterior thalamic nuclei, or the diagonal band of Broca. A significant change in receptor binding was noted only after lesions of the mediodorsal projection, suggesting that cholinergic muscarinic receptors are located on these terminals. These findings suggest that the projection from the diagonal band of Broca which is cholinergic may act as a modulator of the mediodorsal thalamic projection.

Animals

Origin and distribution of noradrenergic innervation in the habenula: a neurochemical study.

The distribution of norepinephrine (NE) was chemically mapped in discrete regions of the rat habenula (Hb). In addition, the contribution of both peripheral sympathetic and central noradrenergic sources to habenula NE was quantified following selective deafferentations. It was found that NE is distributed hetereogeneously in discrete Hb regions. Furthermore, it was demonstrated that after superior cervical ganglionectomy a small (26%) but significant (P less than 0.05) decrease in NE occurred only in the medial Hb (MHb), while NE in the lateral Hb (LHb) remained unaltered. In contrast, deafferentation of central noradrenergic innervation, such as lesions in the ascending dorsal noradrenergic bundle (DNB), caused a marked decrease in NE in both MHb (53%) and LHb (50%). Lesioning the dorsal longitudinal fasciculus resulted in NE loss in both MHb and LHb by 31%. These data corroborate the histofluorescent demonstration of the noradrenergic innervation of the Hb.

Afferent Pathways

Central and peripheral contributions of deafferentation-induced norepinephrine increase in the habenula.

This work examined the contributions of sympathetic and central noradrenergic (NA) innervation to habenular norepinephrine (NE) increase after partial deafferentation. Adult rats received bilateral stria medullaris lesions and after 4 weeks a second lesion was produced which removed bilaterally the dorsal NA bundle or the superior cervical ganglia. The rats were sacrificed 7 days after the second lesion. The data show that strial lesions induced a non-uniform NE increase in discrete habenular regions, which was contributed to by sympathetic innervation in the medial habenula and by central NA projections in both medial and lateral habenular nuclei. It is suggested that NE increase in response to strial lesions is attributed to differential sprouting of peripheral and central NA innervation in the habenula.

Afferent Pathways

Origin of cingulate cortex cholinergic innervation in the rat.

The relative contribution of the n. diagonal band and thalamic nuclei to the cholinergic innervation of the cingulate cortex was examined. Lesions were placed in the n. diagonal band, anterior thalamus, and medial thalamus of rats, and changes in choline acetyltransferase in discrete regions of the cingulate cortex were determined. The n. diagonal band lesion produced a large decrease in choline acetyltransferase activity while the thalamic lesions produced no significant change in activity.

Animals

Regional distribution of catecholamines in nucleus accumbens of the rabbit.

The nucleus accumbens is an important telencephalic region, which is the target limbic and mesolimbic pathways. Because of an ongoing physiological study of the effects of dopamine, we wanted to determine regional differences of dopamine and norepinephrine concentrations in the nucleus. As determined by radioenzymatic assays, dopamine levels were not significantly different in the anterior-posterior dimension, averaging approximately 187 ng dopamine/mg protein. Substantial amounts of norepinephrine were found throughout the nucleus, but the levels were significantly higher in the caudal portions of the nucleus, being approximately 4.5 times higher than in the anterior portions.

Animals

Catecholamines in rat brain following postnatal undernutrition and nutritional rehabilitation.

Norepinephrine and dopamine were examined in 19 discrete brain areas from the telencephalon, diencephalon, and mesencephalon of nutritionally rehabilitated adult rats following postnatal undernutrition from birth through 21 days of age. Following rehabilitation, catecholamine levels were not significantly different from control values in any of the areas examined. Catecholamine concentrations in young, undernourished rats are generally elevated (either from stress or from nutritional insufficiency). Data presented here show that whichever case is true, the early effect of undernourishment is transient and that normal values are restored by nutritional rehabilitation.

Amygdala

Regional mapping of neostriatal neurotransmitter systems as a function of aging.

The purpose of the present investigation was to map chemically the distribution of certain neurotransmitter systems in the neostriatum of rats aged 6, 16, and 26 months. This mapping was carried out by microdissection of discrete striatal regions coupled with radiometric assays for choline acetyltransferase (ChAT), glutamate decarboxylase (GAD), dopamine (DA), and norepinephrine (NA). In all age groups, ChAT, DA, and NA were highest in the rostral relative to the caudal neostriatum. Additionally, ChAT was higher in the lateral than in the medial region, whereas GAD was more homogeneously distributed within the striatum. ChAT activity was decreased significantly primarily in the caudal regions in rats aged 16 and 26 months. DA levels were decreased in the caudal striatum in rats aged 26 months. NA levels were found to be significantly decreased primarily in the rostral neostriatal regions of the oldest rats. GAD activity remained unchanged in all age groups. These regional changes in selected neurotransmitter systems may underlie specific motor and cognitive deficits that often occur during aging.

Aging

Kainic acid-induced neurotoxicity in the striatum: a histofluorescent study.

Histochemical observation of catecholamine terminals in the striatum following kainic acid injections revealed a 'sphere of influence' which contained an increased intensity of dopamine fluorescence as well as non-specific tissue destruction at the injection site. The area of involvement was approximately 50% of the striatum and varied somewhat at any one dose range depending upon the site of injection. It is suggested that destruction of regulatory neuronal systems (cholinergic, GABAergic, peptidergic, etc.) results in a net increase of dopamine in the sphere of kainic acid influence.

Animals