State In Mammals Research Articles

Mammal Sounds and Motivation-Structural Rules: A Test of the Hypothesis

We tested if mammal sounds given in aggressive and fearful/friendly contexts showed acoustic design characteristics in accordance with the Motivation-Structural (MS) rule hypothesis (Morton, 1977). Our data were taken from literature and consist of 76 aggressive sounds and 75 fearful/friendly sounds from 50 species of mammals. Aggressive sounds are of low-frequency and wide bandwidth and thus support MS rule predictions. Fearful/friendly sounds show a trend toward conforming to MS rule design expectations (high-frequency and tonal) but exhibit considerable variation. This variation may be due to the existence of acoustic parameters other than frequency or bandwidth that might convey motivation information in fearful/friendly contexts. In addition, fear and friendliness represent two very different motivation states in mammals and MS rules may not apply to both.

Enhanced response to Con A and production of TCGF by lymphocytes of obese strain (OS) chickens with spontaneous autoimmune thyroiditis.

The mitogenic response to Con A and the production of T cell growth factor or interleukin 2 (IL 2) by splenic and peripheral blood lymphocytes of obese strain (OS) chickens with spontaneous autoimmune thyroiditis have been investigated. By using an optimized method with Con A-coated chicken erythrocytes (MRC), lymphocytes of OS chickens were found to exhibit significantly elevated mitogenic responses as compared with cells from either Normal White Leghorn chickens (NWL) or animals of the Cornell C-Strain (CS), from which the OS has originally been developed. This difference was observed throughout ontogeny up to 15 mo of age, and was associated with increased levels of IL 2 activity in the culture supernatants. The elevated responsiveness of OS T lymphocytes was also found to be manifested in the expression of receptors for IL 2, because Con A-stimulated lymphocytes of OS birds were significantly more effective than those from normal controls in absorbing IL 2 activity from conditioned media (CM) of stimulated spleen cells. High concentrations of CM were suppressive in IL 2 assays, signaling the presence of an inhibitory factor(s) in addition to IL 2. An additional indication for defective immunoregulation was that CM from OS lymphocyte cultures showed significantly less of this suppressive activity in comparison with CM of normal (NWL and CS) lymphocyte cultures. Finally, the spontaneous uptake of 125IUdR of embryonic and early post hatching OS spleen lymphocytes was consistently and significantly enhanced. This difference, however, in contrast to the one observed in Con A responses, was found to decrease with age. The data are discussed in view of the contradictory results concerning T cell functions reported for several autoimmune states in mammals.

Recenzja książki. P. Raths, E. Kulzer, 1976: Physiology of hibernation and related lethargic states in mammals and birds. Bonn. 93 str

Recenzja książki. P. Raths, E. Kulzer, 1976: Physiology of hibernation and related lethargic states in mammals and birds. Bonn. 93 str

Fat metabolism in normal and abnormal states

Various aspects of the use of fatty acids as fuel in normal and abnormal states in mammals are described. The discussion includes use of dietary lipid as fuel, the functioning of adipose tissue as a fuel reservoir, the use of free fatty acids mobilized from adipose tissue as fuel, the liver as a source of lipid fuel, and the use of intracellular lipids as fuel sources. In addition, the responses of lipid metabolism to fasting and exercise are reviewed. Finally, selected data on the effects of infections on the use of lipids as fuels are considered in relation to our current knowledge metabolism.

EFFECTS OF BULBOCAPNINE ON SPINAL REFLEXES OF ANESTHETIZED AND SPINAL RATS

Since all of the so-called “major tranquilizers” have the ability to induce catatonic states in experimental animals, this characteristic pharmacological property is commonly being used as a clue to detecting new compounds in screening tests. However, not all compounds that produce the catalepsy in animals are “tranquilizers”. One remarkable example is bulbocapnine, an alkaloid isolated from Corydalis cava; it was first reported by Peters (1) that a catatonic state in mammals followed bulbocapnine treatment. Although it has been suggested that bulbocapnine catalepsy could serve as an experimental model for schizophrenia or Parkinson's disease, little is known of its effects on the neural components of the motor system. In earlier experiments we found that bulbocapnine selectively depressed the spinal monosynaptic reflex response in the rat with little effect on the polysynaptic neuronal systems (2). These observations have subsequently been confirmed by Willis et al. (3, 4) in the cat. The present report describes a further investigation of the actions of bulbocapnine on spinal reflex systems. The rat was employed in the present experiments so that the electrophysiological data could be accurately compared with the numerous behavioral observations in this species.