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Effects of Food Intake on Cardiac Autonomic Function Reikn Hori, Junichiro Hayano, Seiji Mukai, Takeshi Kamiya, Akira Yamada, Yusaku Sakakibara, Masami Yamada, Takao Fuji- natal, Yosaku Watanabe * and Kazuyuki Takata * ?bird Department ~ff Internal Medicine, Nagoya ('itv Unicersity Medical School Nagoya 46Z and * Toyota ('ollege ~l 7~chnology, I?~vota 471, Japan

l't) investigate changes in hemodynamie regulation with food in take, we studied the power spectral components of heart rate variability in supine and standing position, under controlled respi ration at 15 breaths per minute, 30, 90, 150 and 21(1 minutes after at standard meal, in 6 young healthy male subjects (age range 23-25 years). The respiratory component (0.25 Hz) in the supine position decreased 311 minutes after Food intake, whereas the Mayer wave component ((}.04 (t.15 Hz) in both supine and stand- ing position increased 90 minutes after the meal. The mean RR interval was shortened 30 minutes after the meal both in the standing and the supine posilion, and in the standing position it remained low until 150 minutes after the meal, although there was no effect of food intake on bh)od pressure. These results suggest that the cardiac parasympathetic function decreases 30 minutes after hind intake, whereas the cardiac sympathetic function in- creases 911 minutes after food intake. This may provide a new perspective fl)r understanding the mechanism of postprandial changes in hemodynamic regtdation.

(Thc Autonomic Nervous System, 27:541 546, 19911)

Voiding Dysfunction in Patients with Striato-Nigral Degeneration - Comparison with Parkinson's Disease Ryuji Sakakibara *, Takamichi Hattori *, Keizo Hirayama *, Kosaku Yasuda ** and 'Fomonori Yamanishi ** * Department o f Neutwlo,t,~v and ** Department Of Urology, ('hiha Ibm ersitv School ~ff' Medicine, Chiba 270, .lapan

To investigate tire effect of striato-nigral degeneration on voiding functions wc studied the micturitional histories and carried out urndynamic tests on 14 patients with this disease. Thir teen ()tit o[ 14 patients had micturitional disturbances, One had irritation, 5 had obstruction and 7 had both problems. One patient had uri- nary retention and 6 had urinaw incontinence. Uroflowmetry was performed on 9 patients, and 3 of them had normal flow rates. Ten out of 13 patients with urological signs had residual urine with an average of 125 ml. Urethral pressure profiles were ob- tained from 13 patients: one had high and 2 had low maximum urethral closing pressure. Cystometry was performed in 14 pa lients, and 11 of them had uninhibited cystometrograms, one patient had an autonomous and one an atonic eystometrogram. External sphincter electromyography was perfornred in 14 pa- tients, and 2 had brisk bulbocavernosus reflexes, 3 had absence of anal reflexes, 4 had detrusor sphincter dyssynergia and one had uninhibited sphincter relaxation. Motor unit analysis was per- formed in 6 patients and 3 showed neurogenic changes such as high amplitude a n d / o r polyphasic motor unit potentials.

The results were compared with our previous findings in Parkinsonian patients and they revealed that patients with striato-nigral degeneration had more frequent and more severe voiding dysfunction. The site of lesion involved were not only sites in the central nervous system but also the peripheral sympathetic and somatic nervous system regulating the function of the lower urinary tract,

(The Autonomic Nervous System, 27: 547-551, 1990)

Vasodilator Responses in the Hippocampus in Response to Stimu- lation of the Septal Complex Are Well Maintained in Aged Rats Wei Zhou, Wci-Hua Cao and Akio Sato DtTmrtment ~ff Physiology, Tokyo Metropolilan Institute ~l (iero~l- tology, Tokyo 1 Z~, Japan

The effect ol focal stimulation, either electrical or chemical, oi the septal complex (i.e., the medial septal nucleus and the nucleus of the diagonal band) on the regional hippocampal ccrehrat blood fh)w was examined using laser Doppler flowmetry in healthy adu[l (3-4 months old) and aged (28-29 months old) male Wistar rats anesthetized with urethane. Electrical stimulation of the septal complex produced a current-dependent increase in hippocampal bh)od flow in both the adult and the aged rats. Microinjection ol L-glutamate (50 nmol/l(10 nil into the septal complex also pro- duced an increase in hippocampal blood flow in both groups t',I animals. There were no significant differences between adult and aged rats with respect to the increase in hippocampal blood flov, induced by either electrical or chemical stimulation of the septal complex. The results suggest that the cholinergic vasodilator re sponses of the hippocampal blood flow to stimulation of the septal complex arc well maintained in old age.

(The Autonomic Nerv~ms System, 27:552 557, 19911)

Central Effect of Calcium on Sympthetic Nervous System and Vasopressin Release Hiroshi ltoh, Kazuo Takeda, Ken Takenaka, Toshiyuki l'akesako, Motoo l 'anaka, Masahiro Hirata, Shinichi Tanabe, Telsuo Nakata, Shingo Kawasaki, ,lunko Hayashi, Susumu Sasaki and Masao Nak- Llgttwtl ,~t'('olld [)('l)(Irl/tl('tll Ol Medicm(', Kyoto l~reti'ctual I ;mt c~:~itv of Medicine, Kvoto 602, Japatt

To determine whether calcium ions can modulate centrally the sympathetic nervous system and vasopressin release to cause ear diovascular changes, calcium was injected in the cerebral ventri- cles (i.c.v.) of awake rats, CaC[: (i.c.v.) produced dose-dependent vasodepressor responses. At the dose of 1 /zmol CaCI 2 these responses peaked 10 minutes after the injection and returned to the pre-injection [eve[ within about 20 minutes. The response was accompanied by a fall fir heart rate. The vasodeprcssor response was significantly reduced by intravenous (i.v.) hexamethonium. Propranolol (i.v.) inhibited the hradycardic responsc induced by CaCI z (i.c.v.) without affecting the vasodepressor rcsponsc. In contrast, atropine did not affect the cardiovascular response to i.e.v, calcium. Intravenous t reatment with a vasopressin antagonist proh)nged the vasodepressor response and significantly reduced lhe bradycardic response. The findings suggest that calcium in- duced in the central nervous system a vasodepressor and a brady- cardic response in awake rats. As to the underlying mechanisms, following i.c.v. CaCI e injection the sympathetic nervous system was inhibited and vasopressin was released. The bradycardic re- spouse may be due to the suppression of beta-stimtdation and to the actkm of vasopressin.

(Fhe Autonomic Nervous System, 27: 5(~7-571, 19901