Charles G. Wilber

Some characteristics of the guinea pig electrocardiogram

Abstract The time-relations of the electrocardiograms of normal, male guinea pigs are given. The data are in agreement with previous work with the exception of a longer P wave. In the relationship of Q-T duration to heart rate, using the equation Q-T = K·√R−R, K was found to equal 7.94 ± 0.81. There was no evidence of correlation between heart rate and body weight in these animals.

Some physiological characteristics of the heart of the toadfish,Opsanus tau

A study was made of the heart fromOpsanus tau using an electrocardiograph to record normal activity and the responses to drugs and to experimental manipulations. Bradycardia occurs in toadfish kept out of water for more than 5 minutes. Large doses of darstine, an atropine-like drug, bring about A-V dissociation and prolongation of conduction time, probably by direct action on the heart muscle. Changes in temperature modify the heartin vitro andin situ.

Hematology in the normal male guinea pig

Abstract Normal hematological values for mongrel, male guinea pigs are given. A comparison with values found in the literature showed slightly higher erythrocyte and lower leukocyte levels, higher proportion of lymphocytes, and lower proportions of other cells in the differential count.

The effect of violent exercise on tissue glycogen in albino mice

Abstract Albino mice were forced to swim to exhaustion in water baths of different temperatures. Histochemical and microchemical analyses of various tissues from exercised and control mice were made. There was found a positive correlation between the following: bath temperature and swimming time; liver glycogen and body weight; muscle and liver glycogen. Negative correlations were found between liver glycogen and bath temperature; liver glycogen and swimming time. Muscle glycogen is held relatively constant after the first twenty minutes of swimming.

Response of heart in two new world monkeys to hypothermia

Abstract 1. 1. Male specimens of the genera Ateles ater and Cebus apella were used to study the effect of hypothermia on the heart. The heart was monitored using a direct-writing electrocardiograph. Needle electrodes were devised to fit the small limbs of the animals. Recordings were made in restrained and unrestrained animals at body temperatures which varied from 35°C down to 25°C. 2. 2. The results indicated that heart rate varies inversely with body temperature. There were some differences between the two species, but in general the responses were similar. 3. 3. The relationship of the QT interval to the total cycle length was calculated using the square root formula. When the logarithm of K was plotted against the logarithm of the heart rate a straight line was obtained showing that K decreases with higher heart rates. The slope for Cebus data is steeper than for Ateles. 4. 4. There was virtually a linear prolongation of the T wave as body temperature and heart rate decreased. The so-called Q10 law receives little support from the data.