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Biomedical subjects

A Yuhara

Publications and source records attributed to A Yuhara.

5 recordsLinked to original sources
PubMed2001

PACAP has a neurotrophic effect on cultured basal forebrain cholinergic neurons from adult rats.

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a member of the vasoactive intestinal polypeptide gene family (VIP) that was originally isolated from rat hypothalamus. The high affinity PACAP receptor, PAC1, is expressed in the basal forebrain area of adult, as well as developing rat brain. Hippocampus, a targeting area of basal forebrain cholinergic neurons, contains PACAP. Thus, hippocampal-derived PACAP may have an effect on basal forebrain cholinergic neurons. Indeed, we have reported that PACAP showed neurotrophic effects on these neurons in embryonic and early postnatal culture. Here we report that PACAP has a neurotrophic effect on adult cholinergic neurons in culture. PACAP increases the number of choline acetyltransferase immunoreactive neurons about 2-fold. A similar effect was observed on treatment with cAMP analogue but not nerve growth factor. PACAP also improved the survival and neurite outgrowth of total neurons. These results indicate that PACAP acts as a neurotrophic factor even on adult neurons in vitro.

Age Factors↗
PubMed2000

Pituitary adenylate cyclase-activating polypeptide promotes the survival of basal forebrain cholinergic neurons in vitro and in vivo: comparison with effects of nerve growth factor.

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a member of the vasointestinal polypeptide gene family for which neurotrophic activity has been postulated. PACAP mRNA is expressed in the developing and adult hippocampus, which is the principal target region of septal cholinergic neurons. We therefore studied the effects of PACAP on septal cholinergic neurons. In primary cultures from septum of embryonic and postnatal rats, PACAP increased the number of neurons immunohistochemically stained for the low-affinity nerve growth factor (NGF) receptor p75 and for the enzyme choline acetyltransferase (ChAT). PACAP also caused a corresponding increase in ChAT activity. In comparison, NGF had a greater effect than PACAP on the number of p75- and ChAT-positive neurons in these cultures. In vivo, following fimbria fornix transection, the number of immunohistochemically stained septal cholinergic neurons fell significantly to 18% in rats given continuous intracerebroventricular infusion of vehicle, whereas in rats given NGF the number of these neurons did not differ significantly from unoperated controls. In PACAP-treated rats the number was 48% of unoperated values, which represented a significant increase compared with vehicle-treated rats and a significant decrease compared with NGF-treated rats or unoperated controls. Double-staining experiments revealed that most ChAT-positive neurons in rat medial septum also express PACAP receptor 1. Together the results show that PACAP promotes the survival of septal cholinergic neurons in vitro, and after injury in vivo, suggesting that PACAP acts as a neurotrophic factor influencing the development and maintenance of these neurons.

Acetylcholine↗
PubMed1987

Use of transrectal radial scan ultrasonography in evaluating the extent of uterine cervical cancer.

Transrectal radial scan ultrasonography has been performed in 180 cases of stage Ib, IIa, or IIb uterine cervical cancer. Increases in the parametrial length, width, their product, and internal echo intensity as well as shift of the cervix to the side of more severe induration have been demonstrated, irrespective of the presence or absence of menstruation, as the clinical infiltration becomes more severe. Furthermore, concerning the presence or absence of histologic infiltration, there is a very strong possibility of a cancerous infiltration in cases of mass formation in the parametrium.

Adult↗