We evaluated the effect of electrode montage on the spectrum of the infant auditory brainstem response (ABR). Spectral profiles of ipsilateral, contralateral, noncephalic, and horizontal recordings obtained in response to slow and fast repetition rates and at low and high stimulus intensities were also evaluated. Findings indicate that the spectrum of the infant ABR is dominated by low-frequenc...

The nature of age-related improvements in auditory sensitivity was explored by comparing behavioral and auditory brainstem response (ABR) thresholds in 3- and 6-month-old infants and in adults. Thresholds were estimated for tone pips at 1, 4, and 8 kHz, presented at a rate of 13.3/s. The time course of development of the two response measures was compared, and the correlation between thresholds...

Some basic pharmacological differences between isolated human cerebral and digital arteries obtained at postmortem have been studied. Spiral strip responses were measured isometrically and cumulative drug dose-response curves obtained. Contractile responses were sought to norepinephrine, 5hydroxytryptamine, angiotensin, histamine, KCI, BaCl2 and prostaglandin F2o. Relaxation responses (either b...

Dopamine, via activation of D1 receptors, enhances N-methyl-d-aspartate (NMDA) receptor-mediated responses in striatal medium-sized spiny neurons. However, the role of specific NMDA receptor subunits in this enhancement remains unknown. Here we used genetic and pharmacological tools to dissect the contribution of NR1 and NR2A/B subunits to NMDA responses and their modulation by dopamine recepto...

Achillea santolina, Nepeta cataria and Salvia bucharica are mainly known to possess antispasmodic use in traditional medicine. The essential oils from these plants were screened for their possible pharmacological activity with possible mode of action explored. Volatile oil was extracted by steam distillation using standard procedure given in British Pharmacopoeia 2001. For pharmacological activ...

The pharmacological actions of opiate drugs are best characterized by sedation, analgesia, respiratory depression and changes in temperature. Repeated exposure to opiates, however, produces tolerance to these effects such that the magnitude of response is much reduced or absent. From this it must be assumed that the binding of opiates to their receptor sites activate certain biochemical events ...

The effects of rise time and center frequency on the auditory brainstem response (ABR) elicited by high-frequency tone bursts were examined in six normal-hearing adults. Tone bursts with rise times of 0.1, 0.25, 0.5, and 1.0 msec, duration of 2 msec, and center frequencies of 8, 10, and 12 kHz were used in this study. The absolute latencies of waves I, III, and V were obtained in all subjects, ...