Interruption of the lordosis reflex of female rats by ventral midbrain stimulation.

The lordosis reflex, dorsiflexion of the vertebral column, is an estrogen-dependent, essential element of female sexual behavior in rodents. Unilateral electrical stimulation of the midbrain ventral tegmental area through a chronically implanted electrode in freely moving, estrogen-primed ovariectomized female rats caused a rapid and strong suppression of the lordosis reflex in response to either male mounts or manual cutaneous stimuli. The interruption occurred in a graded manner to increased stimulus intensity, with a threshold at 30 microA. The optimal frequency was at 75-125 Hz. After the termination of electrical stimulation, lordosis performance returned promptly to the pre-stimulation level. No aversive response accompanied the blockade of lordosis. Electrical stimulation specifically blocked lordosis, without disrupting the proceptive components of female sexual behavior. In 10 animals tested, concomitant injection of dopamine receptor blocker pimozide tended to offset the effects of electrical stimulation in 2 cases. Interruption of the lordosis reflex might be mediated by projections from the ventral tegmental area, which activate a descending pathway inhibitory to the lordosis reflex arc at or below the lower brain stem.

[A case of adult type of anomalous origin of left coronary artery from pulmonary artery--with a referential consideration to the disease in Japan].

A case of a 33-year-old man with anomalous origin of the left coronary artery from the pulmonary artery (ALCP) was reported with a referential consideration to the adult type of ALCP previously reported in Japan. The patient visited our hospital for further examination of cardiac murmur detected on a mass physical checkup. He was found to have a continuous murmur, the loudest in the left sternal border of 3rd intercostal space, and developed evidence of ischemia during the exercise stress test in the ECG leads of L2, L3, aVF, and V2 through V6. In addition, studies using echocardiography and color Doppler-echocardiography detected a hypertrophied intraventricular septum and a pattern of turbulent blood flow in the proximal pulmonary artery. Cardiac catheterization and aortography proved the existence of ALCP with a markedly developed collateral circulation from the right coronary artery to the left coronary artery. After surgical restoration by ligating the anomalous opening of the left coronary artery, and by bypass grafting to the left coronary artery, it was clear that dilation and kinking of the right coronary artery was lessened and hypoperfusion in the anterior left ventricular wall was improved. As far as we know, this case is the 35th of adult type ALCP reported in our country. Results from this case and others suggest that early detection and therapy for adult type ALCP is important from the point of view preventing ischemic progression, and indicate that restoration by ligation and bypass grafting may be one of the effective surgical procedures for ALCP.

[Coronary venous oxygen saturation dynamics during intracoronary infusion of ergonovine or acetylcholine in vasospastic angina].

We investigated changes in coronary venous oxygen saturation (CSO2-Sat) dynamics during intracoronary infusion of ergonovine (ERG) or acetylcholine (ACh) in patients with vasospastic angina. In 16 patients with suspected vasospasm in the left coronary artery, intracoronary ERG injection provoked vasospasm in 4 out of 6 patients, and intracoronary ACh in 6 out of 11 patients. A gradual decrease in CSO2-Sat, anteceding angina and ischemic ECG evidence, was characteristic in ERG-induced vasospastic patients, while no significant change of CSO2-Sat was observed in non ERG-induced patients. Intracoronary infusion of ACh was followed in all 11 patients by a transient increase in CSO2-Sat, suggesting decreased myocardial oxygen extraction due to increased coronary blood flow with ACh. However, earlier and sudden decreases in CSO2-Sat below the control levels were characteristic in 6 patients with ACh-induced vasospastic angina. These findings suggest that effects of ERG and ACh on coronary flow dynamics are essentially different although both drugs can provoke vasospasm.

[Evaluation of myocardial oxygen extraction dynamics in syndrome X by continuous measurement of coronary sinus oxygen saturation and its relation to clinical features].

We investigated the relation of myocardial oxygen extraction dynamics to pathophysiology and clinical features in syndrome X. In patients with syndrome X who underwent cardiac catheterization, coronary sinus oxygen saturation (n = 21) during rapid atrial pacing loading was continuously measured using a fiberoptic catheter system, and global and regional left ventricular function (n = 14) was evaluated before and immediately after pacing loading. Results were as follows: 1) In 5 of 21 patients with syndrome X, coronary sinus oxygen saturation during pacing loading fell less than 5% below the baseline without any impairments of global and regional left ventricular function. 2) In 16 patients with syndrome X, coronary sinus oxygen saturation during the pacing loading continuously fell over 5% below the baseline accompanied by impairment of both global and regional left ventricular function. The decrease in regional wall motion of the left ventricle was mainly observed in the apical area. These findings imply that changes in myocardial oxygen extraction dynamics in syndrome X during rapid atrial pacing may show the extent of a patchy area where myocardial oxygen demand-supply imbalance occurs due to coronary microcirculatory disturbances.

IgA nephropathy and Henoch-Schönlein purpura nephritis with anterior uveitis.

Two patients with IgA nephropathy and a patient with Henoch-Schönlein purpura nephritis each associated with anterior uveitis are described. As anterior uveitis accompanying IgA nephropathy improved, renal manifestations were relieved. The patient with Henoch-Schönlein purpura nephritis suffered from not only anterior uveitis but also keratitis. It is suggested that immune mechanisms which induce IgA nephropathy may play a role in the development of anterior uveitis and keratitis.