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The authors studied the distribution of met-enkephalin, α-endorphin, β-endorphin and LHRH within the central nervous system of rats by the indirect immunofluorescent technique, and observed α-endorphin-like immuoreactivity in the median eminence adjoining the portal vein as nerve terminals of dot-like immunofluorescence. This finding deserves special attention since α-endorphin has been considered physiologically inactive. Nerve terminals of α-endorphin-, β-endorphin- and met-enkephalin-like immunoreactivities were immunohistochemically confirmed in the medial hypothalamus. These results positively suggested that this area was playing comprehensive roles in physiological functions of the hypothalamo-pituitary system.To visualize neuropeptide-containing nerve cell bodies, we applied the immunofluorescent technique on various neuropeptides to intraventricularly colchicine injected rats. Some LHRH and met-enkephalin containing nerve cell bodies were observed without colchicine, though. All of substance P-, LHRH- and met-nekephalin-positive nerve cell bodies were visualized in the ventromedial hypothalamic nucleus, substance P- and β-endorphin positive nerve cell bodies in the arcuate nucleus, substance P-positive ones in the posterior hypothalamic nucleus and met-enkephalin-positive ones in the dorsomedial hypothalamic nucleus. Besides, substance P-containing and metenkephalin-containing nerve cell bodies were coexisting in the mesencephalic central gray matter. α-Endorphin-containing nerve cell bodies were also noticed in the caudate nucleus.In addition, calcitonin-like immunoreactive cell bodies were observed in the anterior lobe of the pituitary body.

We performed light and electron microscopic autoradiography of GABA and opiate receptors using 3H-muscimol and 3H-DAMA.Light microscopically, distribution of muscimol and DAMA binding sites was demonstrated by means of Texture Analysing System (Leitz).For electron microscopic autoradiography, selection of development method is important. The authors obtained silver grains in a pattern precisely localized to the cytoplasmic membrane, i.e, the receptor site by means of EAA development.We observed 3H-muscimol binding site in the neuropiles of the cerebellar molecular layer and the substantia nigra ultrastructurally. Receptor sites labeled with silver grains were located not only on the synaptic regions but also on the plasma membranes of the dendrites and axons not corresponding to synaptic sites. 3H-DAMA binding sites in the caudate nucleus and the amygdaloid nucleus were noted on the plasma membranes of the axons, dendrites and nerve cell somas, some corresponding to synapses, others not. Autoradiographical observation of neurotransmitter receptors has still problems to be solved. Nevertheless, this technique is very important to observe the morphological relationship between transmitters and their receptor sites.

The authors observed substance P-, somatostatin- and β-endorphin-like immunoreactivities ultrastructurally in the perikarya of the primary sensory ganglion cells by means of Nakane's enzyme-labeled antibody technique. As the results, the immunoreactivities of the neuropeptides were observed as irregularly shaped masses always encapsulated with membrane-bound contours of which diameters were 200nm to 2μm. Such neuropeptide-containing immunoreactive masses encapsulated by the membrane were usually seen in the vicinity of the Golgi apparatus. These immunoreactivities of the neuropeptides were more often observed in smaller nerve cells, though they were sometimes observed in the larger ones, too.The authors also observed substance P- and somatostatin-like immunoreactivities in the Rexed's lamina II in the posterior horn of the spinal cord as nerve terminals. Substance P- and somatostatin-containing nerve terminals were often stained diffusely by positive immunoreactivity and within them there were denser immunoreactive vesicles uniform in size. These electron dense vesicles with positive immunoreactivity were noted along the nerve axon to the terminal.

Genetic studies were made in 120 males and 92 females of 408 constituents of 22 pedigrees of familial amyloid polyneuropathy (FAP) originated from Ogawa Village area, Japan. The results were as follows. 1) The ages at the onset ranged from 20 to 68, and the mean age was 35.38 in males and 37.88 in females. 2) The cumulative morbid risk ratio was high as 0.8 and above. 3) The penetrance was very high,i.e. 100% when calculated from parents' side and 99.29% from children's side. No skipping of generations was noticed except a case in which the determination of “affected” or “non affected” was impossible. 4) The segregation ratios were 34.67±27.50% as calculated by a single selection and 45.80±2.86% by a complete selection. 5) The transmission mode of FAP originated from Ogawa Village, Japan was autosomaly dominant.

Some of the calcium antagonists with diverse structures are considered to specifically block voltage dependant calcium ion channels of excitatory membranes. Each drug acts on a specific site of the calcium ion channel. Receptor binding experiments with use of tritiated Ca antagonist make it possible to examine the functional sites of these drugs. In this paper, we performed binding experiments and autoradiographic studies Ca ion channel antagonist binding sites using tritiated nitrendipine(NTD) in the rat brain. Brain P2 fraction was prepared, and saturation analysis and kinetic studies at the temperature of 0°C, 25°C and 37°C were performed. In addition, competitive studies by various Ca antagonists were done. The in vitro autoradiographic study was done as follows: After cryostat sections of the rat brain were incubated with 2nM 3H-NTD, a tritium sensitive film was apposed on the slides in the dark and stored for 4 weeks at 4°C. As control, experiments were done with sections to which 10#x2212;5 M nifedipine was added at the same time. As preliminary experiments of autoradiography, saturation analysis on cryostat sections at 0°C was done, with results showing a Kd value of 60pM. Autoradiographic studies of 3H-NTD revealed that specific binding sites were diffusely distributed in the neuronal elements with dominancy in the superior colliculus, hippocampus and interpeduncular nucleus.