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At least 19 recordsLinked to original sources
PubMed1977

[The topography and cytoarchitectonic of the diencephalon of the cow (Bos taurus var. domesticus L.). II. The internal structure of the diencephalon of the cow (Bos taurus var. domesticus L.) (author's transl)].

The five parts of the diencephalon of the cow are distinctly separated by fibrous tractuses or plates. The three main tractuses (Fornix, Tractus mamillo-thalamicus and Fasciculus retroflexus) are very strongly developed. Regarding the essential fibrous structures and the cytoarchitectonic features 62 nuclei can be differentiated in either half of the diencephalon, of which the thalamus contains 28 and the hypothalamus 23 nuclei. Epithalamus, Metathalamus and Subthalamus possess 2 big nuclei on each side. The findings are briefly compared with the data on the diencephalic structures of cow, sheep goat, pig and dromedar given in literature.

Animals↗
PubMed1977

[The topography and cytoarchitectonic of the diencephalon of the cow (Bos taurus var. domesticus L.) I. The topography of the diencephalon of the cow. (Bos taurus var. domesticus L.) (author's transl)].

The study contains a comprehensive review of the literature on the brain of the cattle, followed by notes on form and location of the brain in the skull of the cow and of the diencephalon. In addition we point to some possibilities for locating the brain by stereotaxic manipulations. Several structural particularities are discussed, where to a limited extent references to structures of the brains of other domestic artiodactyla are made.

Animals↗
PubMed1979

Sex hormones metabolism in the brain: influence of central acting drugs on 5 alpha-reduction in rat diencephalon.

Rats after adrenalectomy-testectomy showed a gradual increase in diencephalon 3-oxo-5 alpha-steroid: (acceptor) delta4-oxidoreductase (5 alpha-reductase) activity for 3 days. The activity then returned near to the normal range on the 4th postoperative day. When rats were given testosterone propionate (TP) 3 days after adrenalectomy-testectomy, diencephalon 5 alpha-reductase activity returned to the preoperative range 2 hr after TP administration. Diencephalon 5 alpha-reductase activity showed a highly significant increase (p less than 0.01) after a single administration of carbamazepine, reserpine, diazepam, phenytoin, phenobarbital or disulfiram. A significant increase (p less than 0.05) was also found after a single administration of methylphenidate, caffeine or methamphetamine. Plasma testosterone decreased concurrently after administration of all these agents, except diazepam. Diencephalon enzyme activity decreased significantly after repeated disulfiram administrations (p less than 0.01) but increased significantly after methamphetamine administrations (p less than 0.05). Plasma testosterone showed a tendency to decrease after repeated methamphetamine administrations but tended to increase after repeated disulfiram administrations.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMedDate not supplied

Distribution of oxytocic and vasopressor activity in the rat diencephalon.

The oxytocic and vasopressor activity was studied in five 1 mm thick, horizontal sections of the rat diencephalon. The diencephalon was cut frozen in dry ice. The sections obtained from identical parts of the diencephalon of 10 rats were homogenized together in 0.9% NaCl solution acidified with glacial acetic acid. The homogenate was heated to 100 degrees C for 5 min and centrifuged. The oxytocic activity of extracts was determined in vitro by, the method of Holton using the rat myometrium. The vasopressor activity was determined in vivo recording blood pressure in the carotid artery of rat by the method of Dekańaski. Oxytocic activity was found in all five sections of diencephalon and vasopressor activity in only two sections. The first section included the median eminence and ventral hypothalamus together with the supraoptic nucleus, the second section included the the dorsal hypothalamus with paraventricular nucleus, the third section--the ventral thalamus, the fourth section--the middle part of thalamus, the fifth section--the dorsal thalamus.

Animals↗
PubMed1979

The chemoarchitectonics of the diencephalon of frog (Rana tigrina).

The study deals with the distribution of acid and alkaline phosphatases, ATPase, 5-nucleotidase, nonspecific esterase, specific cholinesterase, and beta-galactosidase in the diencephalon of the frog. The highlights of the present study are the following: i) Acid phosphatase is present in all the neurons, whereas the tracts and commissures are completely negative. ii) Most of the tracts and commissures are positive for 5-nucleotidase. This confirms the author's previous findings that the tracts and commissures of all the areas of frog brain are intensely positive for 5-nucleotidase. iii) beta-galactosidase activity in the nuclei of the diencephalon is either mild or completely absent, whereas the commissures and tracts show positive activity. iv) Habenulothalamic connections are intensely positive for specific cholinesterase and non-specific esterase, moderately positive for beta-galactosidase and completely negative for other enzymes. v) The epiphysis (pineal organ) shows intense reaction for adenosine triphosphatase, acid phosphatase, and 5-nucleotidase and moderate reaction for alkaline phosphatase and non-specific esterase. In contrast to the above enzymes, the specific cholinesterase and beta-galactosidase are completely missing. vi) Lateral forebrain bundles are completely negative for all the enzymes except alkaline phosphatase and beta-galactosidase. The distribution of these enzymes has been correlated with the functional aspects of various nuclei, tracts, and commissures of the diencephalon of the frog.

Acid Phosphatase↗
PubMed1979

Quantitative changes in the fundamental structural pattern of the diencephalon among primates and insectivores.

The volumes of the main components of the diencephalon from 10 basal insectivores, 12 prosimians, and 15 simians including man were compared. The comparison of the percentage composition within the diencephalon shows that the thalamus and the subthalamus increase whereas the epithalamus and the hypothalamus decrease in relative size among primates. The allometric analysis reveals that, in spite of a relative reduction, the epithalamus and the hypothalamus are also progressive structures. However, their allometric size increase, being especially accentuated in earlier phyletic phases, is small in comparison to that of the thalamus and the subthalamus. These latter two components are characterized by a continuous phylogenetic growth from the basal insectivores to the simians. The correlation analysis shows that the strongest correlations and, in many cases, that isometric size increase exist between structures which belong to the same functional system. These findings indicate the existence of at least two major developmental gradients in the quantitative development of the diencephalon, a neencephalic and a limbic one.

Animals↗
PubMed1976

[Topography and cytoarchitecture of the diencephalon in the female comestic cattle (Bos taurus var. dom.)].

Ten brains of cows were, immediately after slaughter, embedded in celloidin, sliced, and stained to visualise neurocytes and nerve fibres, with the view to elucidating the structures of bovine diencephalon. Macroscopically, the diencephalon of cow is characterised by a comparatively strong epithalamic part, large laterally supported Corpora geniculata lateralis, pronounced ventricular bulgings, almost complete fusion of thalami with Massa intermedia, and very large pituitary gland. The five compartments of bovine interbrain are strongly developed and clearly delimitated by fibrous strings and platelets. By due consideration of the major fibre structures and cyto-architectonic characteristics, 62 nuclei may be differentiated in either half of the diencephalon, with 28 being situated in the thalamus and 23 in the hypothalamus. Two nuclear regions each were recordable from the epithalamus, metathalamus, and subthalamus.

Animals↗
PubMed1976

[Variations of the glucose 6 phosphodehydrogenase activity at the level of the diencephalon and of the gonads of the dormouse (Glis glis L.) during the annual cycle].

Activity levels of G6-PDH in the diencephalon and testes of Glis glis during the annual cycle show comparable variations. In the autumn, this activity is low and the gonads are inactive. At the anset of hibernation, this activity increases and becomes maximal during the period preceeding awakening. At mid-hibernation, the seminiferous tubules display in important enzymatic activity. Awakening is marked by a fall in enzymatic activity level that is a little more precosius of the diencephalon. The variations of enzymatic activity levels of G6-PDH in the diencephalon are similar in the female with an autumnal minimum and a maximal activity at the end of hibernation.

Animals↗
PubMed1977

The effect of some phenylethanolamine N-methyltransferase inhibitors on the adrenaline content in the domestic fowl diencephalon.

The concentration of adrenaline in the domestic fowl diencephalon was determined by a mass spectrometric or fluorimetric method. The values obtained were 701 and 803 ng/g, respectively. The administration of phenylethanolamine N-methyltransferase (PNMT) (EC 2.1.1.28) inhibitors (SK&F 7698 or SK&F 64139) to the domestic fowl produced a marked reduction in the diencephalic noradrenaline methylation (from 25% in the controls ot 7--8% in the PNMT-inhibitor-treated animals); the large decrease in adrenaline concentration (to 14--18% of controls) was accompanied by a moderate decrease in noradrenaline concentration (to 63--84% of controls). Reserpine, in contrast, produced a marked reduction of both adrenaline and noradrenaline (to 12 and 17% of controls, respectively) but did not affect the percentage of methylation. It would seem a reasonable assumption that in the domestic fowl diencephalon, adrenaline is formed by N-methylation of noradrenaline and functions there as a transmitter in some specific adrenergic neuronal pathways.

Animals↗
PubMedDate not supplied

Role of computerized transverse axial tomography on stereotactic surgery of the diencephalon. A preliminary report of 67 cases.

67 cases of various functional disorders of the diencephalon were examined by EMI scanner. The patients were composed of 38 cases of parkinsonism, 7 cases of thalamic syndrome, 6 cases of choreoathetoid movement, 2 cases of dystonia, 11 cases of involuntary movement of unknown etiology and 1 case of torticollis, tic, and ballismus, respectively. In parkinsonism, 79% showed diffuse cerebral atrophy, 5% had focal low density in the substantia nigra and the thalamus, whereas 16% remained normal. Pre- and postoperative assessment with CT scan was briefly discussed with reference to stereotactic surgery of the diencephalon.

Adult↗
PubMed1979

"The diencephalon of Ptilocercus lowii (pen-tailed tree-shrew)".

The pen-tailed tree-shrew (Ptilocercus lowii) has been regarded by Le Gros Clark (1926), and Martin (1968) to possess more primitive morphological and to a certain extent, neuro-anatomical characteristics than the other tree-shrew species belonging to the sub-family Tupaiinae. Investigations have been carried out on the diencephalon of Ptilocercus lowii which has not been completely done by Le Gros Clark and other workers since 1926, to find out whether the diencephalon has actually undegone any phylogenetic changes that should be more advanced than those of the Insectivora or remain more primitive than that of the Tupaiinae. The diencephalic structure that show the most significant phylogenetic features which differe Ptilocerecus from Tupaia are observed in the anterior, dorsolateral and ventrolateral thalamic groups, and the geniculate bodies. The nucleus anteroventralis is, by comparison, much smaller and poorly differentiated from the nucleus anteromedialis. The nucleus anterodorsalis is also comparably large and does not reach the dorsal surface of the thalamus as it does in the primates. The midline nuclei do not show any significant differences, except the notably larger size of nucleus parataenialis in Ptilocercus. The nucleus mediodoralis is small and indifferentiated although it does show some incipient signs of cellular differentiation. The nucleus centralis lateralis is well developed; its inferior (ventral) part is larger than its superior part which is the better developed of the two parts in the tupaiids and primates. The nucleus centrum medianum appears to be very small and forms only a lateral extension of the nucleus parafascicularis. The ventrolateral thalamic group basically consists of nuclei ventrales anterior, lateralis and posterior without intermediate or transitional zones as found in Tupaia and Primates. The nucleus pretectalis is the largest and the best developed of all the elements of the posterior thalamic nuclear group. The lateral geniculate nucleus is not differentiated into laminae like that in Tupaia and Primates; it is merely a homogeneous structure that appears to be smaller in size that the pregeniculate and medial geniculate nuclei. The medial geniculate nucleus is large in proportional size of the whole thalamus and appears to be well differentiated cellularly into several small parts. No remarkable changes are noted in the epithalamus, subthalamus and hypothalamus. However, the nucleus ventromedialis appears to be the most outstanding structure in the infundibular region of the hypothalamus. The mammillary region is of a simpler construction in Ptilocercus than in Tupaia; it does not protrude from the ventral surface of the hypothalamus. In the light of these findings, the phyletic status of Ptilocercus in the family Tupaiidae is discussed.

Animals↗
PubMed1976

Immunohistochemical studies on the localization and distribution of monoamine neuron systems in the rat brain. I. Tyrosine hydroxylase in the mes- and diencephalon.

The localization and distribution of tyrosine hydroxylase (TH), the first enzyme in the catecholamine synthesis, in the mes- and diencephalon has been studied with the indirect immunofluorescence technique of Coons and collaborators. Principally, TH was present in neuron systems with a distribution similar to known dopamine, noradrenaline and adrenaline systems. The present data, taken together with published and some unpublished results, indicate that all parts of most central dopamine neurons, i.e. cell body, dendrites, axon and nerve terminals, appear strongly fluorescent. The adrenaline neurons also appeared strongly fluorescent, except for their axons, which only exhibited a weak fluorescence. Only cell bodies of noradrenaline neurons were strongly fluorescent, whereas the nerve terminals and axons showed a weak or moderate fluorescence intensity. The fine noradrenaline nerve terminals in some areas, such as the thalamus, were invisible or, under favourable conditions, weakly fluorescent. Therefore, in the present study we are mainly dealing with the dopamine neurons of the upper brain stem. Our results demonstrate a widespread occurrence of TH-positive neuron systems in the mes- and diencephalon. The different mesencephalic dopamine systems and their ascending projections were visualized. Numerous TH-positive cell bodies were present along the ventricle system extending from the aqueductus cerebri to the most cranial periventricular parts of the third ventricle. The caudal part of these neurons, consisting of very small cell bodies, belong to the dorsal periventricular system described by Lindvall and Björklund. Several TH-positive cell bodies were also observed in the inferior collicle of young animals. In the superficial layers of the inferior collicles TH positive nerve terminals were seen. At the hypothalamic level the A11 to A14 cell groups as well as some additonal cell bodies and extensive nerve terminal plexuses appeared strongly fluorescent. The differences in the intensity of the TH-related immunofluorescence between various brain regions and between various neuron systems may well reflect differences in enzyme levels between the various catacholamine systems rather than be due to the existence of different types of TH.

Adrenergic Fibers↗
PubMed1977

Formaldehyde-induced fluorescence in the telencephalon and diencephalon of the eel (Anguilla anguilla l.). A fluorescence-microscopic and microspectrofluorometric investigation with special reference to the innervation of the pituitary.

In the telencephalon and diencephalon of the eel (Anguilla anguilla L.) formaldehyde-induced fluorescence was studied microscopically and microfluorometrically with special emphasis on the innervation of the pituitary. In the telencephalon fluorescent fibers contained predominantly noradrenaline fluorophores. Fluorescent nuclei could not be established. In the diencephalon fluorescent perikarya were found in: (1) the paraventricular organ (PVO), possessing either dopamine or, to a lesser extent, serotonin fluorophores; (2) the PVO-accompanying group, exhibiting spectral data resembling those of noradrenaline fluorophores; (3) the nucleus hypothalami anterior (NHA), a small paired group of catecholamine-containing cells posterior to the commissura transversa.--The nucleus lobi inferioris exhibited a high density of delicate, most probably dopamine-containing terminals, while fibers surrounding this nucleus contained noradrenaline fluorophores. A high density of fluorescent terminals containing dopamine and/or noradrenaline was found in the habenular complex. Fluorescent terminals in the pituitary contained fluorophores resembling either dopamine or noradrenaline. Fluorescent tracts entered the pituitary from different directions. A rostral, unpaired tract enters the neurointermediate lobe, as also verified experimentally. The rostral pars distalis receives two paired tracts, one from a rostral and one from a dorsal direction. The proximal pars distalis also receives two paired tracts, one from a dorsal and one from a posterior direction.

Anguilla↗
PubMed1977

Topographical distribution of acetylcholinesterase and butyrylcholinesterase in the diencephalon and mesencephalon of the garden lizard (Calotes versicolor).

The present report incorporates the histochemical mapping of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) among the various nuclei and fiber tracts of the diencephalon and mesencephalon of Calotes veriscolor. The various nuclei, for both enzymes, present varying degrees of staining, ranging from negative nuclei, on the one hand, to mild and intense staining on the other hand. Almost all of the fiber tracts reveal intense activity in BChE preparations, while they demonstrate mild and moderate activities for AChE. The nature of the various nuclei in relation to enzymatic patterns is discussed.

Acetylcholinesterase↗
PubMed1975

Somatosensory cerebral evoked potentials after vascular lesions of the brain-stem and diencephalon.

Clinical and electrophysiological observations are described in 7 patients with clinically well-identified vascular lesions of the brain-stem or diencephalon. In the patients of Group A with a thalamic syndrome, the somatosensory cerebral evoked potentials had a reduced voltage and increased latency on the affected side. No significant anomalies were recorded in the patients of Group B with a Wallenberg or Weber syndrome. In patients of group C with a locked-in syndrome, the cerebral evoked potentials presented marked bilateral anomalies which provided interesting data about the extension of the pontine vascular lesions into the tegmentum. The pathophysiological mechanisms involved in the changes of average cerebral evoked potentials and in the slowing of corticipetal conduction are discussed.

Adult↗
PubMed1977

Immunoreactive luteinizing hormone releasing factor (LRF) in pituitary stalk plasma from female rats: effects of stimulating diencephalon, hippocampus and amygdala.

1. Previous studies on the effect of preoptic and median eminence stimulation on the immunoreactive LRF content of pituitary stalk blood from pro-oestrous rats have been extended. Stimulation of the suprachiasmatic nuclei and anterior hypothalamic area produced increments in LRF which were 66 and 18% respectively, of that produced by preoptic stimulation, and 38 and 9%, respectively, of that produced by stimulation of the median emience. Stimulation of the amygdala and hippocampus had no effect. 2. The LRF response was not affected significantly when preoptic stimulation was accompanied by stimulation of the hippocampus. 3. In animals subjected to section of the dorsal afferents of the diencephalon, the LRF response to preoptic stimulation was similar to that in intact rats. However, the facilitatory effect of oestrogen on the LRF response to preoptic stimulation was significantly reduced in the roof sectioned compared with intact animals. The post-operative resumption of oestrous cycles was delayed but not abolished by dorsal deafferentation.

Amygdala↗
PubMed1979

Brain stem, cerebellum and diencephalon of the marmoset (Callithrix jacchus).

The gross anatomy and the internal structure of the marmoset (Callithrix jacchus) brain stem, cerebellum and diencephalon are described based on the observations made on the material obtained from 10 adult animals (native name: sagui). 5 brains were used for gross anatomical observations; the other 5 brains, included in toto in celloidin, were cut into serial sections, properly stained and used for comparative studies of the internal structure. Only general descriptions are given considering this part of the encephalon because, in further papers, it is intended to go on describing in details the nervous system of this small primate, very common in Brazilian jungles and easily domesticated. It shows to be a very good and inexpensive animal for neurophysiological experiments.

Animals↗