Chronic restraint stress produces retraction of apical dendrites of pyramidal neurons in medial prefrontal cortex. To begin to examine the functional significance of this dendritic reorganization, we assessed the effects of chronic restraint stress on a prefrontally mediated behavior, extinction of conditioned fear. After bar press training to obtain a baseline of activity against which to meas...

Incipient freeze-thaw stress in onion bulb scale tissue is known to cause enhanced efflux of K(+), along with small but significant loss of cellular Ca(2+). During the post-thaw period, irreversibly injured cells undergo a cytological aberration, namely, ;protoplasmic swelling.' This cellular symptom is thought to be caused by replacement of Ca(2+) from membrane by extracellular K(+) and subseq...

Germinating conidiospores of Neurospora crassa that were exposed to 45 degrees C, a temperature that induces a heat shock response, were protected from injury caused by freezing in liquid nitrogen and subsequent thawing at 0 degrees C. Whereas up to 90% of the control spores were killed by this freezing and slow thawing, a prior heat shock increased cell survival four- to fivefold. Survival was...

Changes in freezing injury percentage, lipid peroxidation (malonaldehyde formation), antioxidant enzymes activity and proline content were monitored in the leaves of olive cvs. ‘Fishomi’ and ‘Roughani’ under diff erent freezing temperatures (-5, -10, -15 and -20°C for 10 h). Th e results showed that freezing injury (determined by electrolyte leakage analysis) and malonaldehyde (MDA) content of ...

Freezing is a defensive response to acute stress that is associated with coping and alterations in attentional processing. However, it remains unclear whether individuals in high risk professions, who are skilled at making rapid decisions in emergency situations, show altered threat-induced freezing. Here we investigated the effect of incident experience in a high risk profession on freezing. A...

Attempts to cryopreserve oocytes by freezing have, to date, been based mostly on empirical approaches rather than on basic principles, and perhaps in part for this reason have not been very successful. Theoretical considerations suggest some fairly ‘heretical’ conclusions. The concentrations of permeating cryoprotectants employed in past studies have probably been inadequate, and the choice of ...

Although corticotropin-releasing hormone (CRH), a regulator of stress responses, acts through two receptors (CRH1 and CRH2), the role of CRH2 in stress responses remains unclear. Knock-out mice without the CRH2 gene exhibit increased stress-like behaviors. This profile could result either directly from the absence of CRH2 receptors or indirectly from developmental adaptations. In the present st...

Cold stress impairs plant growth and development, resulting in crop failure. Cultivated potato (Solanum tuberosum L.) is sensitive to freezing, while its wild relative, S. commersonii, has a strong freezing tolerance. To decipher the anti-freezing mechanism of CM, we carried out transcriptomic metabolomic analysis an variety CM (a type commersonii) freeze-sensitive DM Solanum L.). A total 49,23...

freezing stress affected some vital processes of plant, and causing disturbance on the plant growth. in order to study the effect of low temperatures on freezing tolerance of chickpea (cicer arietinum l.) a factorial experiment with 4 replications carried out using 3 chickpea genotypes (mcc496، mcc763 and mcc798) and 7 freezing temperatures (-4, -6, -8, -10, -12, -14 and -160c). explants were c...