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Biomedical subjects

S Tei

Publications and source records attributed to S Tei.

14 recordsLinked to original sources

Morphogenesis of the frontal organ in Bufo bufo during development.

Morphogenesis of the frontal organ in Bufo bufo was examined under transmission electron microscope. Many remarkable similarities to the frontal organ of other Amphibia Anura are observed. It originates from a diverticulum in the dorsal region of the neural tube. It is egg-shaped, has an eccentric lumen, and is made up of three kinds of cells: 1) photoreceptors, which protrude into the lumen; 2) supportive cells; and 3) ganglion cells, which make synaptic contact with the photoreceptors. Peculiar to Bufo bufo is the melanin-like pigments around the light-sensitive part of the photoreceptors. These pigments may prevent light dispersion. The frontal organ in Bufo bufo starts degenerating during the early premetamorphic stages.

Animals

[Pharmacological properties of procaterol, a newly synthetized, specific beta 2-adrenoceptor stimulant. Part I. Effects on the CNS (author's transl)].

Effects of procaterol (PRO) on the CNS were investigated in comparison with those of salbutamol (SAL) and isoproterenol (ISO). PRO, 15 to 50 mg/kg given subcutaneously suppressed spontaneous movement in mice, rats and rabbits and with a large dose, 1000 mg/kg, the animals became quiet and immobile. In dogs, PRO produced similar symptoms and in addition, there was nausea and vomiting. The animals recovered within 3--8 hours. ID50's in depressing spontaneous movement were 20.2 and 245 mg/kg for PRO, 51.1 and 133 mg/kg for SAL and 2.37 and 143 mg/kg for ISO, respectively, both by the subcutaneous and oral routes of administration. Methamphetamine induced increase in motility and fighting behavior was also suppressed by PRO when similar doses were given. PRO had no effect on coordinating movement, halothane anesthesia, drug and electric stimulation induced convulsions and body temperature, and there was no muscle relaxant action. However, PRO in large doses prolonged sleeping time with hexobarbital. The analgesic effect of PRO was not observed with Haffner's and Landall Selitto's methods but acetic acid induced writhing was suppressed by PRO. PRO had little effect on spontaneous EEGs either cortical or from deep structures, and EEG arousal responses. The effects of PRO on the CNS were slight and nonspecific, and similar to those of SAL and ISO.

Adrenergic beta-Agonists

[Pharmacological properties of procaterol, a newly synthesized, specific beta 2-adrenoceptor stimulant. Part II. Effects on the peripheral organs (author's transl)].

Pharmacological properties of procaterol (PRO) in the peripheral organs were examined in comparison with those of sulbutamol (SAL) and isoproterenol (ISO). PRO slightly enhanced twitch tension of the tibialis anterior muscle but affected little the mono- and poly-synaptic spinal reflexes and ganglionic transmission. PRO depressed spontaneous contractions of the isolated ileum, non-pregnant and pregnant uterus and also the gastrointestinal and uterine movements in vivo. PRO prolonged the time of peroral charcoal transport in the intestine. Potencies of PRO in producing these effects were between those of ISO and SAL except those on the uterus in which PRO was more potent than ISO and SAL. Pro depressed gastric and bile secretion but had no effect on pancreatic secretion. ISO, PRO and SAL reduced resistance of the common carotid, femoral and renal arteries and the relative potencies of PRO and SAL to ISO were significantly less in the renal artery than in the other arteries. In accelerating heart rate in conscious rats and dogs, PRO (p.o. or s.c.) was almost equipotent to SAL. Urine flow, GFR, RPF, free water and osmolar clearance and also excretion of electrolytes were reduced by PRO with the concomitant fall of systemic blood pressure. PRO has no effect on blood coagulation and hemolysis but inhibited carrageenin edema and an increase in permeability of blood vessels induced by acetic acid. PRO had no alpha-adrenolytic, cholinolytic and anti-histaminic effects.

Adrenergic beta-Agonists

Isomers of erythro-5-(1-hydroxy-2-isopropylaminobutyl)-8-hydroxycarbostyril, a new bronchodilator.

The isomers of erythro-5-(1-hydroxy-2-isopropylaminobutyl)-8-hydroxycarbostyril (1), a new potent and beta2-selective bronchodilator, were synthesized by optical resolution of compound 1 and inversion of the erythro to the threo isomers. The isomers were tested for activities to inhibit histamine-induced bronchospasm and to increase the heart rate of anesthetized dogs. Racemic and (-)-erythro-1 showed potent and beta2-selective bronchodilater activities. Among the isomers, (-)-erythro-1 showed the highest activities and (+)-erythro-1 showed the lowest.

Animals