Pelvic Electric Potential as a Marker of Autonomic Dysfunctions and Risk Factor of Neurogenic Arrhythmias in Humans.

Differential high-resolution ECG (V1-V2) and pelvic electric potential measured between the coccyx and perineum were recorded simultaneously in resting supine position in men with autonomic nervous system disorders (N=37). In healthy volunteers (N=23), the effective (rms) value of PEP presented by median and interdecile range was 30 (20-80) µV within the frequency band of 0.03-80 Hz. In patients, the corresponding value was significantly higher: 140 (80-280) µV. In both groups, the amplitude harmonic spectrum of pelvic electric potential decreased monotonically with frequency according to 1/f1.6 law. In some patients (N=16), rare single or grouped high-amplitude impulses (up to 1 mV) of pelvic electric potential with total duration of about 1 sec were observed; of them, some persons (N=7) demonstrated practically one-to-one synchronous relations between these impulses and arrhythmia episodes indicating abnormal activity of the autonomic nervous system as their most probable common cause. The high-amplitude pelvic electric potential impulses were also observed in ECG records as interference signals with an amplitude attaining 50 µV. Thus, high-resolution ECG and pelvic electric potential can reveal the risk of abnormal neurogenic influences on the heart. The data obtained are discussed in relation to diagnostics of the autonomic nervous system disorders, neurogenic arrhythmias, and risk of sudden cardiac death.

Ischemia in pelvic organs as an independent pathogenic factor in the development of benign prostatic hyperplasia and urinary bladder dysfunction.

Blood supply to the pelvic organs of outbred male rats was diminished by graduated constriction of the distal part of the inferior vena cava. Deficiency of intramural blood supply in prostate and urinary bladder was revealed by bioimpedance harmonic analysis according to the magnitude of first cardiac peak in the bioimpedance spectrogram. In 1-1.5 months, the histological examination revealed the glandular-stromal form of progressive benign prostatic hyperplasia in all ischemic rats. The development of hyperplasia was not accompanied by the changes in testosterone, dihydrotestosterone, or estradiol in blood and prostatic tissue. Assessment of vesical functional status by recording the intravesical pressure during infusion cystometry revealed an increase in the amplitude of spontaneous fluctuations of detrusor tone and intravesical pressure during bladder filling, which can be considered as indicator of detrusor hyperactivity. The data conclude that chronic ischemia of pelvic organs is an individual pathogenic factor in the development of benign prostatic hyperplasia and associated urinary disorders.

[Coherence and phase analysis of theta-oscillations in the septohippocampal system during seizures].

Interrelations of the hippocampus and medial septal area (MSA) in the theta band (4-8 Hz) were studied during seizures produced by electrical kindling in waking guinea pigs. Field activity (EEG) was analyzed using the wavelet transform. A decrease in coherence of theta-oscillations in the hippocampus and MSA was observed during seizures. Phase analysis showed that in the beginning of kindling the MSA led in phase, but after formation of the pathological focus, MSA lagged the hippocampus. The data may contribute to understanding mechanisms of temporal lobe epilepsy.