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T Ueha

Publications and source records attributed to T Ueha.

At least 73 records · Page 4Linked to original sources

GABA-stimulated 36Cl- influx into reconstituted vesicles with purified GABAA/benzodiazepine receptor complex.

Solubilized and Purified gamma-aminobutyric acid (GABA)A receptors from membrane vesicles of the bovine cerebral cortex were reconstituted into phospholipid vesicles and 36Cl- influx into the vesicles was examined. GABA induced a significant stimulation of the 36Cl- influx into reconstituted vesicles with 1.5% CHAPS/0.15% asolectin solubilized receptor and flunitrazepam further enhanced the GABA-stimulated influx. The purification of GABAA/benzodiazepine receptor complex and Cl- channel solubilized by 1.5% CHAPS/0.15% asolectin from membrane vesicles was achieved by 1012-S affinity column chromatography. The reconstituted vesicles with the purified receptor complex and Cl- channel also exhibited GABA-stimulated 36Cl- influx. This GABA-stimulated influx of 36Cl- was also enhanced by flunitrazepam, while suppressed by bicuculline, a GABAA receptor antagonist. These results strongly suggest that GABAA receptor is directly coupled with Cl- channel, whereas benzodiazepine receptor may be functionally coupled with GABAA receptor and modulates the GABA-stimulated Cl- influx through GABAA receptor. The present results also indicate that the purified GABAA receptor complex is coupled with Cl- channel and possesses functional characteristics as GABAA receptor.

Animals↗

Androgen responsiveness of proteinase F in the submandibular salivary glands of inbred mice.

Using the radioimmunoassay technique, we studied androgenic regulations of proteinase F in the submandibular salivary glands (SMG) of various mouse strains (ICR, BALB/CA, C3H/HeN, C57BL/10N, and DBA/2N). The proteinase contents in BALB/CA and DBA/2N mice were almost the same between males and females. However, prominent sex differences in enzyme content were seen in all other strains; i.e., male glands of C3H/HeN and C57BL/10N contained more proteinase F than female glands did. On the contrary, the enzyme level in the ICR was exceedingly higher in females than in males. The enzyme contents in ICR SMG increased in males following castration and decreased after androgen injection in both castrated males and normal females. On the contrary, the enzyme level in C3H/HeN was decreased by castration and increased by androgen injection. Therefore, these sex differences in ICR and C3H/HeN mice depend on androgen, though the direction of the response is opposite.

Animals↗

Immunocytochemical study of proteinase F in the mouse submandibular gland.

Esteroproteinases extracted from the submandibular gland (SMG) of normal male mice were fractionated by isoelectric focusing into three major peaks with isoelectric point (pI) values of 9.9 (P-esterase), 5.8 (proteinase A), and 5.6 (proteinase D). In castrated males or normal females, an additional esteroproteinase with a pI of 4.6 (proteinase F) appeared. By single radial immunodiffusion analysis using a specific anti-proteinase F serum, the proteinase F content in females or castrated males was found to be 15 times as high as that in normal males. These facts suggest that the synthesis of proteinase F is inhibited by androgens. Immunocytochemical localization of proteinase F in the SMG was examined by indirect enzyme-labeled antibody and ferritin-labeled antibody methods for light and electron microscopy, respectively. Castration of normal males caused morphological changes in granular convoluted tubular (GCT) cells, i.e., GCT cells with both several small secretory granules in their apical region and some striations at their basal region (light cells) were observed in addition to typical GCT cells. Immunoreactive proteinase F was exclusively localized in such small secretory granules of the light cells, but was only minimally present in large secretory granules of the typical GCT cells. In females, however, uniform localization of proteinase F among secretory granules of all GCT cells was observed. It is suggested that the small secretory granules in light cells are formed after castration.

Animals↗

Inhibitory effect of androgen on the synthesis of proteinase F in the male mouse submandibular gland.

Androgenic regulation of one of the esteroproteinases (proteinase F) in the mouse submandibular gland was studied using specific antiserum. In contrast to esteroproteinases such as proteinases A, D or P-esterase, proteinase F content in male but not in female mice was increased by gonadectomy and decreased by the injection of various androgens. In-vivo incorporation of [3H]leucine into proteinase F in males was increased after castration and decreased by the injection of testosterone propionate; androgens inhibited the de-novo synthesis of proteinase F in male mice. The dose-response curves for testosterone propionate and time-courses following castration or after the injection of testosterone propionate were reciprocal between proteinase F and total esteroproteinase activity. Proteinase F, like other esteroproteinases in the submandibular gland of the mouse, was localized in granular convoluted tubular cells. These data indicate that granular convoluted tubular cells of the male mouse submandibular gland synthesize both androgen-inducible proteinases and androgen-inhibitory proteinase (proteinase F).

Androgens↗

A new esteroproteinase (proteinase F) from the submandibular glands of female mice.

One of the esteroproteinases present in the submandibular glands of female mice was purified and characterized. The enzyme, designated proteinase F in this report, had a pI value of 4.6 and a molecular weight of 27600, being comprised of two subunits of 10000 and 18000 daltons. The amino acid composition of proteinase F resembled that of the epidermal growth factor-binding protein, but antiserum against proteinase F only reacted weakly against the binding protein. Proteinase F had an optimum pH at around 9.0 and was strongly inhibited by Cu2+ and Hg2+ (42 and 76% inhibition, respectively, at a concentration of 4 x 10(-6) M). It was also inhibited by aprotinin, phenylmethylsulfonylfluoride, iodoacetamide, leupeptin, antipain, and benzamidine but neither by trypsin inhibitors from pancrease, soybean, or ovomucoid, nor by TLCK, TPCK, and epsilon-amino-n-caproic acid. Although its actual physiological function has yet to be determined, these properties indicate that proteinase F is a new enzyme, being distinguished from known proteinases, kallikrein, plasmin, trypsin, chymotrypsin, tonin, angiotensin-converting enzyme, proteinase A (beta-nerve growth factor endopeptidase), proteinase D (epidermal growth factor-binding protein), P-esterase, renin A, and renin C. Proteinase F was present in the submandibular glands of female mice more abundantly than in those of males, but it increased in males following castration. Thus, proteinase F appears to be affected by male hormones in vivo.

Amino Acids↗

Characterization of two esteroproteases from the male mouse submandibular gland.

Three major esteroproteases, proteases A and D and P-esterase, obtained from the glands were studied kinetically and chemically; two (proteases A and D) were identified. Protease A is composed of a single subunit, molecular weight (27,600) similar to the native molecule (27,000); protease D consists of three subunits, approximate molecular weights of 9200, 7600 and 4600. P-esterase contains two subunits, approximate molecular weights of 7100 and 14,000. Protease A exhibits a strong kinin-releasing activity; the other two enzymes have low activity. Protease D binds to low molecular weight-epidermal growth factor, forming a complex which has an electrophoretic mobility similar to that of high molecular weight-epidermal growth factors. When beta-nerve growth factor was incubated with protease A, the amino-terminal amino acid, serine, was lost from the growth factor and a new amino-terminal amino acid, methionine, appeared. These data indicate that proteases D and A are the same proteins as epidermal growth factor-binding protein and beta-nerve growth factor endopeptidase, respectively. From a comparison of the peptide maps of trypsin-digests of the enzymes, the proteases A and D were inferred to have a similar primary structure.

Animals↗

Induction of various androgen-dependent esteroproteases (trypsin-like and chymotrypsin-like enzymes) by tri-iodo-L-thyronine in the submandibular glands of female mice and mice with testicular feminization.

Trypsin-like and chymotrypsin-like esteroprotease isozymes of the mouse submandibular gland were separated by isoelectric focusing. In normal female mice the following pI-isozyme activities were found; pI-4.6, -5.6 (shoulder), -5.8, -7.1, and -9.9, hydrolytic activities for benzoylarginine ethylester (BAEE) (trypsin-like enzymes), and pI-4.7 and -10.3 hydrolytic activities for acetyltyrosine ethylester (ATEE) (chymotrypsin-like enzymes). In mice with testicular feminization (Tfm mice), only pI4.6 hydrolytic activity for BAEE was found; no ATEE hydrolytic activity was detected. In normal female mice, both 5 alpha-dihydrotestosterone (5 alpha-DHT) and tri-iodo-L-thyronine (T3) significantly increased all these isozymes except the pI-4.6 hydrolytic activity for BAEE. In Tfm mice, T3 also increased all these isozymes except the pI-4.6 hydrolytic activity for BAEE, but 5 alpha-DHT had no effect on any enzymes. These results suggest that the pI-4.6 hydrolytic activity for BAEE is non-inducible by the two hormones. Androgen does not seem to be involved in the inductions of these esteroproteases by T3.

Androgen-Insensitivity Syndrome↗