Electronic system for the obtention of phase plane curves for action potentials.

This system is designed for the amplification of the bioelectrical signal, obtention of its derivative in respect to time, automatic brightness control for both beams of the oscilloscope, and stability. The system includes a central measuring section which is a modified Tektronix oscilloscope type 565. Automatic control of brightness as a function of sweeping speed allows photographic recordings.

Programmed stimulator for threshold of action potential.

A programmed digital stimulator is described, in which the pulse generator can be regulated in frequency and duration. The output pulses amplitude increases automatically by increments under 5% of the previous step, sequence which allows a much better approximation to the threshold value of action potential. A photographic camera is synchronized for recording.

The fine structure of the epithelial cells of the mouse prostate. II. Ventral lobe epithelium.

The fine structure of the epithelial cells of one component of the prostatic complex of the mouse-the ventral lobe-has been investigated by electron microscopy. This organ is composed of small tubules, lined by tall simple cuboidal epithelium, surrounded by smooth muscle and connective tissue. Electron micrographs of the epithelial cells of the ventral lobe show these to be limited by a cell membrane, which appears as a continuous dense line.