Diencephalon

Brain structure below the thalamus and main portion of the ventral region of the diencephalon, controlling homeostatic and nonhomeostatic basic body and brain functions, including circadian and feeding rhythms, energy metabolism, thermogenesis, sympathoadrenal, and neuroendocrine outflow (secretion of hormones by the pituitary gland), behavioral state and memory functions. 

Fig. 8.1 Rostrocaudal neuroanatomical distribution of CCR5-immunoreactivity in the telencephalon, diencephalon and mesencephalon using a CCR5 antibody (Santa Cruz Biotechnology, Santa Cruz, CA, USA). Regions corresponding to pictures are depicted in coronal diagrams taken from the Paxinos and Watson (1998). (a, b) M Motor cortex, (c, d) CPu caudate putamen (striatum), (e,t)SID substantia innominata dorsal part, (g, h) GP globus pallidus, (i, j)Me medial amygdaloid...

Anden, N.E. Dahlstrom, A. Fuxe, K. Larsson, K. Olson, L. and Ungerstedt, U. Ascending monoamine neurons to the telencephalon and diencephalon. Acta Physiol Scand 67 313-326, 1966. 

Muller F. and O Rahilly J. (1988). The development of the human brain, including the longitudinal zoning the diencephalon at stage 15. Anat Embryol 179, 55-72. 

Berlanga M., Simpson T., Alcantra A. (2005). Dopamine D5 receptor localization on cholinergic neurons of the rat forebrain and diencephalon a potential neuroanatomical substrate involved in mediating dopaminergic influences on acetylcholine release. J. Comp. Neurol. 492, 34-49. 

Diencephalon Thalamus lateral and medial habenular nuclei... 

Textbooks on neuroscience often describe the location and function of hundreds of individual brain regions (see references above). However, for current purposes these will be kept to a minimum (Figure 2.1). Anatomically, the brain can be subdivided into the forebrain containing the telencephalon and diencephalon, the midbrain or mesencephalon and the hindbrain (metencephalon and myelencephalon). The telencephalon includes the left and right cerebral hemispheres encompassed by the cerebral cortex (neocortex). Cortex is a translation of the word bark and is so-called because its surface, made up of numerous sulci (grooves or invaginations) and gyri (raised areas), is on the outer surface of the brain like the bark of a tree. Each hemisphere is divided into four lobes, named from the front (rostral) to back (caudal) of the brain frontal, temporal, parietal and occipital. 

Ascending Reticular Activating System (ARAS) A network of neurons running up (ascending) through the core of the brainstem to the diencephalon and descending to the spinal cord. Also known as the reticular formation. 

Diencephalon The between brain connecting the midbrain and forebrain which comprises the thalamus and hypothalamus. 

Median forebrain bundle A bundle of monoaminergic neuronal axons travelling from the brainstem through the diencephalon to various limbic structures. 

Histaminergic neurons have been found in the hypothalamus or diencephalon of a variety of vertebrate brains, including those of fish, snake, turtle and bird. The brain histaminergic system of zebrafish has been studied in... 

By immunohistochemistry, a- and p-synucleins are concentrated in nerve terminals, with little staining of somata and dendrites. Ultrastructurally, they are found in close proximity to synaptic vesicles. In contrast,y-synuclein is present throughout nerve cells in many brain regions. In rat, a-synuclein is most abundant throughout telencephalon and diencephalon, with lower levels in more caudal regions. P-Synuclein is distributed fairly evenly throughout the central nervous system, whereas y-synuclein is most abundant in midbrain, pons and spinal cord, with much lower levels in forebrain areas. 

Rosie R, Thomson E, Fink G (1990) Oestrogen positive feedback stimulates the synthesis of LHRH mRNA in neurones of the rostral diencephalons of the rat. J Endocrinol 124 285-289... 

Takahashi, L. K., Lisk, R. D. and Burnett, A. L., 2nd (1985) Dual estradiol action in diencephalon and the regulation of sociosexual behavior in female golden hamsters. Brain Res. 359,194—207. 

It is possible that this compound (and perhaps related compounds) acts by direct entry into the diencephalon. 

In order to test whether water-soluble fullerenes could be potential agents against the treatment of Parkinson s disease and other CNS degenerative diseases related to neuronal apoptosis, the protective effects of water-soluble fullerene derivatives 1 and 6-8 on 6-hydroxydopamine-induced apoptosis of CNS dopaminergic neurons (Silva et al., 2005) in developing zebrafish were investigated. It was demonstrated that 1,6 and 7 were able to protect 42%, 47% and 23%, respectively of total CNS neurons, whereas 1,6 and 8 blocked each with 60%, 100% and 60% of specific dopaminergic neuronal death in the diencephalon as it is exemplarily shown for 8 in Fig. 3.8. 

The diencephalon is composed of several nuclei that are grossly grouped into the thalamus, hypothalamus, epithalamus, and subthalamic nucleus. The thalamus serves as a sensory relay, receiving projections from all of... 

CYPl IB mRNA in frog telencephalon, diencephalon, midbrain, and cerebellum by RT-PCR. In situ hybridization shows CYPl IB mRNA in cells of pallium mediale in telencephalon, nucleus preopticus in diencephalon, stratum griseum superficiale tecti in midbrain, and Purkinje cells in cerebellum (Takase et al., 2002). 

Wisden W, Laurie DJ, Monyer H, Seeburg PH. 1992. The distribution of 13 GABAa receptor subunit mRNAs in the rat brain. I. Telencephalon, diencephalon, mesencephalon. J Neurosci 12 1040-10462. 

Figure 1.2 presents a coronal section through the human brain. In brief, the brain may be divided into the brainstem (consisting of the medulla, pons and midbrain) that is linked to the diencephalon which is composed of the thalamus and the hypothalamus. The two cerebral hemispheres are linked by the corpus callosum, a large tract of nerve fibres that enables the two... 

Hippocampus Region primarily concerned with learning and short-term memory. Hypothalamus Part of the diencephalon comprising several nuclei where hormones such as oxytocin and antidiuretic hormone are S5mthesized and pass to the pituitary gland. Involved in the regulation of the peripheral autonomic system and pituitary hormones such as prolactin, growth hormone and adrenocorticotrophic hormone. 

MPTP) and sodium benzoate induce a strong downregulation in the expression of tyrosine hydroxylase mRNA and in the tyrosine hydroxylase-positive cells in the ventral diencephalon. These chemicals also decreased the expression of the dopamine transporter (DAT), a membrane transport protein involved in dopamine reuptake, that is, a specific marker of dopaminergic neurons [9]. 

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