Kiyoshi Oshima

Neuropeptides in cerebral cortex of macaque monkey (Macaca fuscata fuscata): Regional distribution and ontogeny

The concentrations of vasoactive intestinal polypeptide, somatostatin and substance P were determined in various cerebral subdivisions of adult and foetal Japanese monkeys (Macaca fuscata fuscata) by specific radioimmunoassays. In adult tissues, the highest level of vasoactive intestinal polypeptide was found in the somatosensory cortex and the lowest level in the occipital cortex. A high level of somatostatin was found in the association cortex (prefrontal, parietal and temporal cortex); the lowest level was noted in the occipital cortex. Substance P was found to be high in prefrontal and temporal cortex. The highest levels of substance P and somatostatin were obtained in the amygdala. Between embryonic 4 and 5.5 months, concentrations of peptides increased dramatically, and in the adult, all neuropeptides in cortical subdivisions significantly decreased. By the gel filtration method, only one immunoreactivity which coeluted with substance P and vasoactive intestinal polypeptide was demonstrated in extracts of 4-, 5.5-month-old and adult monkey cerebral cortex. In contrast, somatostatin immunoreactivity eluted as 3 peaks. Almost 80% of the immunoreactivity co-eluted with synthetic somatostatin, regardless of the age of the tissue. The molecular weights of two larger molecules were determined to be 13 and 3 kdaltons.

Ontogeny of somatostatin in cerebral cortex of macaque monkey: an immunohistochemical study.

Distribution of somatostatin-immunoreactive cells in the cerebral cortex of macaque monkeys at embryonic day 120 (E120), E140, newborn, postnatal day 60 (P60) and adult stages were studied by the avidin-biotin-peroxidase immunohistochemical method. At all stages, there existed 3 types of cells in the gray matter: bipolar, multipolar and small-sized cells which stained only in perikaryon. Somatostatin-immunoreactive cells were observed from E120. The cell number increased between E120 and E140 and decreased until P60. At the newborn stage, a high density of cells was distributed in layer II of the prefrontal and parietal cortices (areas FD and PE). In layer I of the postcentral, parietal, temporal and preoccipital cortices (areas FA, PC, PE, TA, TE and OA), small numbers of horizontal cells were detected only at the embryonic and newborn stages. In adulthood, the number of somatostatin cells was much smaller than at the early stages (E140 and newborn). Compared to other cortical areas, in occipital cortex (area OC), there was little change in cell number during development. In occipito-temporal cortices, there were increases in cell number from posterior to anterior portion at all the stages. The large number of somatostatin cells in all layers of the cerebral cortex during the early stages indicates that somatostatin plays a role in the development of the monkey cerebral cortex.

Neuropeptide-immunoreactive cells and fibers in the developing primate cerebellum.

Using the avidin-biotin-peroxide immunohistochemical method, we studied the distributions of somatostatin (SOM)-, cholecystokinin-8 (CCK-8)- and substance P (SP)-like immunoreactivities in the cerebellum of macaque monkeys at embryonic day 120 (E120), E140, newborn, postnatal day 60 (P60) and adults. During the embryonic stages, there were many SOM-, CCK- and SP-immunoreactive structures in the external granular layer, Purkinje cell layer and white matter, SP-immunoreactive mossy fibers and their terminals were distributed in the granular layer and white matter. During these stages, there were SOM-immunoreactive Purkinje cells, Golgi cells and a few cells in the molecular layer, and CCK-immunoreactive Purkinje cells and cells in the molecular layer. At the newborn stage, all of the immunoreactivities in the external granular layer decreased and the number of immunoreactive fibers increased in the white matter. At P60 stage, SOM- and CCK-immunoreactive fibers were observed around Purkinje cells, which seem to be the fiber terminals of basket cells. Many SOM, CCK and SP fibers were distributed in the white matter. In the adult stage, we observed little neuropeptide-immunoreactivity in the cerebellum. The high concentration of the neuropeptide-immunoreactive fibers and cells in the earlier stages suggests that the neuropeptides may be involved in the development of the primate cerebellar cortex.

Ontogeny of cholecystokinin-8 and glutamic acid decarboxylase in cerebral neocortex of macaque monkey

SummaryConcentration of cholecystokinin-8 and the activity of glutamic acid decarboxylase were determined in the various cerebral cortical subdivisions of Japanese monkey (Macaca fuscata fuscata) at three different ages (embryonic 4 months, full-term and adult). The CCK-8 immunoreactive material extracted with 90% methanol from the cerebral cortex of the adult and foetal monkey were shown to be identical with synthetic cholecystokinin-8 by the criterion of co-elution on gel filtration chromatography (Sephadex G-50). The peptide concentration increased dramatically by about 30–80 fold (in terms of protein) and 17–28 fold (in terms of wet weight) between embryonic 4-month-old and full-term monkeys, while the level decreased 1/6–1/16 (protein) and 1/4–1/10 (wet weight) between full-term and adult monkeys. In adults, the highest levels of the peptide was observed in the association cortex, orbital prefrontal cortex and posterior parietal cortex. Glutamic acid decarboxylase activity, on the other hand, gradually increased about 4–10 fold (protein) between embryonic 4-month-old and adult animals and there was little variation in the increase rate among the cerebral subdivisions. In contrast to cholecystokinin-8, no reduction in the enzyme activity occurred between full-term and adult animals. The high level of cholecystokinin-8 in the embryonic period suggests that the peptide may participate in the regulation of the development of primate cerebral cortex.

Ontogeny of substance P, somatostatin and vasoactive intestinal polypeptide in the cerebellum and cerebrum of the chick embryo

Summary The developmental changes of substance P (SP), somatostatin and vasoactive intestinal polypeptide (VIP) were studied in chick embryonic brain tissue by radioimmunoassays. In the cerebellum, SP and somatostatin were present initially (day 10) at high levels, and then rapidly declined to a minimum at hatching. In the cerebrum, VIP was first detectable on day 16, and the level increased through to hatching. The content of somatostatin gradually increased from day 10, while the SP content was constant until day 16 and then increased up to hatching. The SP immunoreactivity of the cerebellum from 10-day-old chicks chromatographed as two peaks on a Sephadex G-50 Superfine column. Most of the activity (75%) eluted at the zone indicating a 13 Kdalton protein; the other peak co-eluted with synthetic SP. The SP immunoreactive materials in the cerebrum chromatographed as a single peak which co-migrated with synthetic SP. In contrast, somatostatin immunoreactive materials in both the cerebrum and cerebellum from 10-day-old chick embryos eluted as three peaks. The major immunoreactivity (over 80%) eluted with synthetic somatostatin and two larger molecules showed molecular weights of 13 and 3 Kdaltons.

Decreased smooth muscle side effects with 16, 16-dimethyl-trans-Δ2-PGE1 methyl ester in Japanese monkey (Macaca fuscata fuscata)

The smooth muscle stimulating activity of a new PGE1 analog, 16, 16-dimethyl- trans delta2 -PGE1 methyl ester (ONO-802) was evaluated by simultaneously recording the EMG of the uterus and intestines, along with urinary bladder pressure, and blood pressure in pregnant and non-pregnant Japanese monkeys (Macaca fuscata fuscata). Single intravenous injections of ONO-802 in increasing dosages (0.2-5 microgram/kg) were found to be 50-100 times or more effective in inducing uterine contraction than PGF2alpha and PGE1. A mild, transient gastrointestinal muscle stimulating activity was observed, but change in urinary bladder pressure and blood pressure was not evident. ONO-802 induced uterine contractions in the pregnant animals were 10 times greater than in the non-pregnant animals. These results suggest that ONO-802 may be a suitable clinical prostaglandin for use in therapeutic abortion.

Absorption of prostaglandin E2 and uterine sensitivity of the non-pregnant and pregnant monkey in vivo

Abstract Radioactive (11- 3 H) prostaglandin E 2 (PGE 2 ) levels in plasma of non-pregnant Rhesus and Japanese monkeys were determined by radioimmunoassay. The amounts of PGE 2 in plasma increased gradually and reached a peak 90 minutes after oral administration. Comparatively low levels were detected 24 hours after oral administration. Plasma PGE 2 levels increased rapidly and disappeared within 5 minutes when 5 μg/kg of PGE 2 was administered intravenously. Uterine contractile sensitivity to PGE 2 and F 2α was measured by the threshold of a venous dosage required to evoke an elevation of uterine contractility in non-pregnant and pre- and post-labor Japanese monkeys. Uterine sensitivity to PGE 2 in the non-pregnant monkey appear to vary in accordance with the sexual life span. At term of pregnancy, PGE 2 was much more potent in causing uterine contraction than PGF 2α . During labor and at postpartum period with lactation, effectiveness of PGE 2 appear to be less than that of PGF 2α . The non-pregnant and pregnant uterus of the third trimester are more sensitive to PGE 2 than the laboring and postpartum uterus. The long latency of the elevation of uterine contractility induced by the intravenous administration of PG suggests that the PG compounds have potent actions on the central nervous system.

Ontogeny of somatostatin in the cerebral cortex of the macaque monkey: An immunohistochemical study

Distribution of somatostatin-immunoreactive cells in the cerebral cortex of macaque monkeys at embryonic day 120 (E120), E140, newborn, postnatal day 60 (P60) and adult stages were studied by the avidin-biotin-peroxidase immunohistochemical method. At all stages, there existed 3 types of cells in the gray matter: bipolar, multipolar and small-sized cells which stained only in perikaryon. Somatostatin-immunoreactive cells were observed from E120. The cell number increased between E120 and E140 and decreased until P60. At the newborn stage, a high density of cells was distributed in layer II of the prefrontal and parietal cortices (areas FD and PE). In layer I of the postcentral, parietal, temporal and preoccipital cortices (areas FA, PC, PE, TA, TE and OA), small numbers of horizontal cells were detected only at the embryonic and newborn stages. In adulthood, the number of somatostatin cells was much smaller than at the early stages (E140 and newborn). Compared to other cortical areas, in occipital cortex (area OC), there was little change in cell number during development. In occipito-temporal cortices, there were increases in cell number from posterior to anterior portion at all the stages. The large number of somatostatin cells in all layers of the cerebral cortex during the early stages indicates that somatostatin plays a role in the development of the monkey cerebral cortex.