Changes of blood pressure and regional blood flow in SART rats and drug actions on these changes

Hata, Taeko; Kita, Tomitaro; Namimatsu, Akio; Itoh, Eiji; Oda, Yasuo

doi:10.1254/fpj.79.335

Cited by 33 publications

(26 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We previously reported that SART (specific alternation of rhythm in temperature)-stressed animals, repeatedly cold-stressed animals with dysautonomia, exhibit increased food intake and locomotor activity (4), decreased blood pressure (5), and hyperalgesia (6). These symptoms correspond to symptoms correlated with decreased levels in brain 5-HT in rats, as described above.…”

mentioning

confidence: 64%

Changes in CNS Levels of Serotonin and Its Metabolite in SART-Stressed(Repeatedly Cold-Stressed)Rats.

1991

Self Cite

View full text Add to dashboard Cite

Central nervous system levels of serotonin (5-HT) and 5-hydroxy indoleacetic acid (5-HIAA) in SART (specific alternation of rhythm in temperature) stressed (repeatedly cold-stressed) rats were examined by HPLC-ECD. In SART stressed rats, the levels of both 5-HT and 5-HIAA decreased in many brain areas. In the spinal cord, only the 5-HT level decreased. Therefore, the ratio of 5-HIAA to 5 HT increased only in the spinal cord. These results suggest that SART-stressed rats have some form of abnormality in the synthetic system of 5-HT.Serotonergic and various other neural sys tems play important roles in pain sensation, behavior, learning and other activities. It has been reported that an increase in the brain level of serotonin (5-HT) coincides with de creases in spontaneous and feeding behavior and an increase in blood pressure in rats (1). It has also been reported that 5-HT levels in crease in the rat hippocampus during acquisi tion trials in learning behavior (2). Decreases in rat brain 5-HT levels lead to increases in spontaneous and feeding behavior and hyper algesia (3).We previously reported that SART (specific alternation of rhythm in temperature)-stressed animals, repeatedly cold-stressed animals with dysautonomia, exhibit increased food intake and locomotor activity (4), decreased blood pressure (5), and hyperalgesia (6). These symptoms correspond to symptoms correlated with decreased levels in brain 5-HT in rats, as described above.In the present study, we examined brain and spinal cord levels of 5-HT and its major metabolite, 5-hydroxyindoleacetic acid (5 HIAA), in SART-stressed rats, using high performance liquid chromatography (HPLC) with electrochemical detector. The relation ship of 5-HT levels to some abnormalities such as impaired passive avoidance and hyperalge sia observed in SART-stressed animals is dis cussed.Male Wistar rats (Japan SLC Inc.) weighing about 250g were used throughout the experi ments.For the loading of SART stress (repeated cold stress), according to our previous report (7), rats were alternately placed into a cold cage set in a room maintained at -3°C and a normal temperature cage set in a room kept at 24°C at 1-hour intervals between 09:00 and 16:00. They were kept in the cold cage from 16:00 to 09:00 the next morning. On and after the 2nd day, animal positions were shifted be tween the two cages according to the same schedule on the 1st day, for five consecutive days. On the 6th day, the stressed animals were used for experiments.For extraction of 5-HT and 5-HIAA from the brain and spinal cord, the rats were sacri ficed by overhead irradiation with 2,450 MHz microwaves at 5 kW for 1.0 sec using a micro wave applicator (Toshiba, TMW-6402 A) be tween 11:00 and 12:00, in consideration of the

show abstract

mentioning

confidence: 64%

Changes in CNS Levels of Serotonin and Its Metabolite in SART-Stressed(Repeatedly Cold-Stressed)Rats.

1991

Self Cite

View full text Add to dashboard Cite

show abstract

“…With respect to the circu latory system of SART-stressed animals, several abnormalities (5,6,8,9) such as a continuous lowering of blood pressure (5), sympathicotonic-type ECG (electrocardio gram) (6), increases in blood flow in the abdominal aorta and superior mesenteric artery, and decreased blood flow in the common carotid artery (5), have been previously reported.…”

mentioning

confidence: 99%

“…There have been numerous reports that SART (specific alternation of rhythm in temperature) -stressed (repeated cold stressed) animals (1,2), vagotonic-type model animals (3) for clinical autonomic imbalance, show various physiological changes (3)(4)(5)(6)(7). With respect to the circu latory system of SART-stressed animals, several abnormalities (5,6,8,9) such as a continuous lowering of blood pressure (5), sympathicotonic-type ECG (electrocardio gram) (6), increases in blood flow in the abdominal aorta and superior mesenteric artery, and decreased blood flow in the common carotid artery (5), have been previously reported.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Changes of Tissue Blood Flow in Mice Loaded with SART (Repeated Cold) Stress or Restraint and Water Immersion Stress and the Effect of Administered Neurotropin

Hata

Kita

Kawabata

et al. 1986

Japanese Journal of Pharmacology

Self Cite

View full text Add to dashboard Cite

Abstract-In order to explore the peripheral microcirculation and to obtain an outline of autonomic innervation in SARI (specific alternation of rhythm in temper ature)-stressed (repeated cold-stressed) animals, which are regarded as model animals for clinical vagotonic-type dysautonomia, peripheral tissue blood flow was determined in mice, using the hydrogen clearance method.SART-stressed mice showed a decrease in gastric blood flow, no change in hepatic blood flow and an increase in dermal blood flow. In the mice exposed to the restraint and water immersion stress (RWIS), a type of acute stress, in contrast with SARI stress which is a subacute type, remarkable decreases were observed in gastric, hepatic and dermal blood flows.Changes of both gastric and dermal blood flow in SART stressed mice were dose-dependently prevented and maintained within normal limits by the treatment with Neurotropin, a sedative analgesic which is an extract isolated from vaccinia virus-inoculated and inflamed skin of rabbits. In RWIS loaded mice, Neurotropin exhibited a great preventive effect on changes of blood flow in the stomach, a slight effect in the liver, and no effect in the cutis. When mice were loaded with SARI stress after left-cervical vagotomy, SARI stress failed to elicit any decrease in gastric blood flow. In SARI-stressed mice treated with 6 hydroxydopamine, gastric and dermal blood flows tended to show a further decrease and increase, respectively, over and above the changes caused by SART stress. From these results, it is suggested that SART-stressed mice may have decreased gastric parasympathetic tone, a decrease in sympathetic tone and also other anomalies such as increased tension of the sympathetic cholinergic vasodilator nerves in the cutis.There have been numerous reports that SART (specific alternation of rhythm in temperature) -stressed (repeated cold stressed) animals (1, 2), vagotonic-type model animals (3) for clinical autonomic imbalance, show various physiological changes (3-7). With respect to the circu latory system of SART-stressed animals, several abnormalities (5,6,8,9) such as a continuous lowering of blood pressure (5), sympathicotonic-type ECG (electrocardio gram) (6), increases in blood flow in the abdominal aorta and superior mesenteric artery, and decreased blood flow in the common carotid artery (5), have been previously reported.

show abstract

“…Abnormalities reported in SART-stressed animals include the cardiovascular system. In conscious SARTstressed rats, resting blood pressure (BP) is lower than that of unstressed rats and hypotension is continuous (6). Reported also are abnormal electrocardiographic changes and increased heart rate (HR) in SART-stressed mice / rats (7 -10).…”

Section: Introductionmentioning

confidence: 99%

Effects of AF-DX116 and Other Muscarinic Receptor Antagonists on Orthostatic Hypotension in Autonomic Imbalanced (SART-Stressed) Rats

Hata

Funakami²,

Itoh³

2005

J Pharmacol Sci

Self Cite

View full text Add to dashboard Cite

Abstract. SART (specific alternation of rhythm in temperature)-stressed rats are an animal model of autonomic imbalance created by exposing animals to repeated cold stress. The SARTstressed rats have been shown to easily develop orthostatic hypotension (OH). In this study, effects of AF-DX116, a selective M 2 antagonist, and other muscarinic receptor antagonists on OH were investigated in SART-stressed and unstressed rats. Each anesthetized rat was canulated into the left common carotid artery, and blood pressure (BP) and heart rate were measured. Stimulation for postural change was initiated by head-up tilting. As the indices of OH, the maximum fall of BP, % reflex (recovery from maximum fall), and the area enclosed between the baseline and the recovery curve for BP (AUC) were used. Large AUC and small % reflex in SART-stressed rats were changed, becoming similar to those of the unstressed rats by AF-DX116 and methoctoramine. Atropine and methylatropine had similar effects to AF-DX116. However, the effects of methoctoramine, atropine, and methylatropine were less than that of AF-DX116. Pirenzepine was not effective. In conclusion, it was suggested in SART-stressed rats that OH was related to hyperactivity in the parasympathetic nerve and the M 2 receptor played the major role in OH.

show abstract

Changes of blood pressure and regional blood flow in SART rats and drug actions on these changes

Cited by 33 publications

References 0 publications

Changes in CNS Levels of Serotonin and Its Metabolite in SART-Stressed(Repeatedly Cold-Stressed)Rats.

Changes in CNS Levels of Serotonin and Its Metabolite in SART-Stressed(Repeatedly Cold-Stressed)Rats.

Changes of Tissue Blood Flow in Mice Loaded with SART (Repeated Cold) Stress or Restraint and Water Immersion Stress and the Effect of Administered Neurotropin

Effects of AF-DX116 and Other Muscarinic Receptor Antagonists on Orthostatic Hypotension in Autonomic Imbalanced (SART-Stressed) Rats

Contact Info

Product

Resources

About