Biomedical subjects

R Ando

Publications and source records attributed to R Ando.

78 records · Page 5Linked to original sources

PubMed1977

[Effects of capsaicin on spontaneous unit discharges in medial thalamic single neurons of cats (author's transl)].

The effect of capsaicin was studied in gallamine triethiodide immobilized adult cats. Single neurons were recorded from the medial thalamus with a stainless steel microelectrode. Out of 21 neurons recorded in this experiment, 10 were responsive to both nociceptive (pinch) and non-nociceptive (hair bending and/or tapping) stimuli. Six neurons were responsive to only non-nociceptive stimuli and 5 were not responsive to these stimuli. Out of 10 neurons responding to both nociceptive and non-nociceptive stimuli, 9 were responsive to both bradykinin (3 microgram) and capsaicin (3 microgram). Out of 6 neurons responding to only non-nociceptive stimuli, 5 were not responsive to either bradykinin and capsaicin. All neurons responding to bradykinin were also responsive to capsaicin. The latency for bradykinin and capsaicin was 7.64 +/- 1.12 sec and 0.97 +/- 0.07 sec, respectively. The increased in firing frequency produced by capsaicin was depressed by morphine. However, these depressant effects of morphine on single unit activity were antagonized by naloxone.

Action Potentials↗

PubMed1976

[Effects of a benzodiazepine derivative, MS4101, on emotional behaviour of untamed cats].

Effects of MS4101 on emotional behaviour in untamed cats were studied and compared with those of diazepam. Offensive behaviour, i.e., whine response to a rod presented in front of the snout and blowing air on back hair was markedly observed, and whine, attacking and biting responses to tapping with a rod on the back in these cats were marked. Defensive behaviour, i.e., hissing, crouching body, ear flattening to blowing air on back hair, a rod presented and tapping was markedly observed. From 30 min after MS4101 and diazepam in doses of 2 approximately 4 mg/kg i.p., offensive behaviour in untamed cats was depressed. ID50 (50% of inhibition dose) of offensive behaviour for MS4101 and diazepam was 2.40 (1.95 approximately 2.95) mg/kg i.p. and 0.96 (0.69 approximately 1.34) mg/kg i.p., respectively. MS4101 and diazepam in doses of 2 approximately 4 mg/kg i.p. decreased the offensive behaviour. ID50 of defensive behaviour for MS4101 and diazepam was 3.00 (2.46 approximately 3.66) mg/kg i.p. and 1.45 (1.14 approximately 1.84) mg/kg i.p., respectively. Both MS4101 and diazepam exhibited muscle relaxant effects. Here, diazepam was more effective than MS4101. ED50 of muscle relaxant activity for MS4101 and diazepam was 4.30 (3.03 approximately 6.11) mg/kg i.p., 7.40 (5.04 approximately 10.66) mg/kg i.p., respectively. A single administration of MS4101 and of diazepam in doses 2 mg/kg i.p. enhanced food intake.

Agonistic Behavior↗

PubMedDate not supplied

The effects of cadmium on a clonal osteogenetic cell, MC3T3-E1: inhibition of calcification and induction of metallothionein-like protein by cadmium.

To clarify the effects of cadmium (Cd) on bone formation, a clonal osteogenetic cell, MC3T3-E1, was used in the present study. After 24 h of culture, Cd at 1 ppm and above decreased DNA synthesis and alkaline phosphatase activity, but Cd at 1.5 ppm caused no significant decrease in collagen content. The cells treated with Cd (0.03-1.0 ppm) for 24 h showed the dose-dependent effects on metallothionein-like protein synthesis. The marked increase of Cd content unbound to metallothionein (MT)-like protein with cadmium at 1 ppm may be responsible for the toxic effects of cadmium. After 10 days of culture, the accumulation of 45Ca to the cell layer decreased with increasing level of cadmium at 0.03 and 0.1 ppm. The cadmium-treated cell layer showed a weaker reaction to histochemical staining for mineral compared with control culture. This result suggests that Cd inhibits an initial process of calcification.

Alkaline Phosphatase↗

PubMedDate not supplied

Diminution of ejaculatory capacity induced by frequent ejaculation in dogs: prevention and reversal by yohimbine.

The effect of yohimbine, an alpha-2 adrenoceptor antagonist, on diminished ejaculatory capacity induced by frequent ejaculation was investigated in dogs. Ejaculation was elicited by manual penile stimulation (for 5 min) 5-8 times every 30 min. The amount of ejaculate produced by the stimulation was drastically reduced during a period of frequent ejaculation in a frequency-dependent manner. When administered immediately after the first ejaculation, yohimbine (0.1 mg kg-1, i.p.) completely prevented the decrease in the amount of ejaculate produced in the succeeding ejaculation. Moreover, similar treatment with yohimbine immediately after the fifth ejaculation when the dogs displayed a greatly reduced ejaculatory capacity restored the capacity to the initial level. In addition, yohimbine increased the total number of sperm produced during a period of frequent ejaculation. These data corroborate our previous finding that yohimbine at a low dose has a stimulatory effect on ejaculatory function in dogs. The present study also indicates that an alpha-2 adrenergic mechanism may be involved in the diminution of ejaculatory capacity induced by frequent ejaculation.

Animals↗

PubMedDate not supplied

Differential effects of yohimbine, naloxone and 8-OH-DPAT on ejaculatory response in male dogs.

The aim of this study was to compare the effects of the alpha(2)-adrenergic-receptor antagonist yohimbine, the 5-HT(lA)-receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) and the opioid-receptor antagonist naloxone (all of which have been shown to stimulate male sexual arousal/motivation in rats) on sexual responses in male dogs. Sexual responses (i.e., ejaculation, penile erection and pelvic thrusting behavior) were elicited by manual penile stimulation. Systemic administration of yohimbine (0.03-1.0 mg/kg) produced a biphasic dose response curve for the amount of ejaculated semen collected during genital stimulation (for 5 min), whereas 8-OH-DPAT (0.03-0.3 mg/kg) dose-dependently decreased the amount of ejaculated semen. Thus, yohimbine increased the amount of ejaculated semen at lower doses (0.03-0.3 mg/kg), but decreased it at the highest dose (1.0 mg/kg). The highest dose of yohimbine (1.0 mg/kg) and 8-OH-DPAT (0.3 mg/kg) also produced a significant delay of onset in both ejaculation and penile erection latency (time from starting the stimulation to the first ejaculation and full erection), and a decrease in the incidence of pelvic thrusting behavior. In contrast, administration of naloxone (0.03-1.0 mg/kg) did not affect the sexual responses elicited by genital stimulation. These results indicate that yohimbine and 8-OH-DPAT, but not naloxone, affect sexual responses, particularly ejaculation, and that the drugs which stimulate the mechanisms regulating sexual arousal/motivation in male rats do not show identical effects for sexual function in male dogs. The present findings also confirm our previous observations that the ejaculatory capacity in dogs can be stimulated by lower doses of yohimbine, as evidenced by an increase in the amount of ejaculated semen.

8-Hydroxy-2-(di-n-propylamino)tetralin↗

PubMedDate not supplied

Massive pulmonary hemorrhage in polyarteritis nodosa (PN); report of a case.

We report a case of massive pulmonary hemorrhage which emerged in the course of polyarteritis nodosa (PN). Pulmonary hemorrhage was the major manifestation which determined the mortality of this patient, though severe renal failure concurrently developed. The diagnosis of PN should be considered in all cases of pulmonary hemorrhage coexisting with renal failure. As pulmonary hemorrhage can be life-threatening, early diagnosis is essential for the prompt start of adequate therapy.

Acute Kidney Injury↗