Inhibition of the LH Surge by Restraint Stress in Cyclic Rats: Studies on the Role of GABAA and GABAB Receptors

There is evidence that stress can alter the activity in the brain of gamma-aminobutyricacid (GABA), a neurotransmitter that has been implicated in the regulation of LH secretion. In the present study the role of GABA in the restraint stress-induced inhibition of the LH surge was investigated in the intact cyclic rat. Intracerebroventricular (icv) administration of the GABAA receptor agonist muscimol (0.1, 0.5 or 1 μg) 5 min before the presumed onset of the pro-oestrous LH surge (at 0900 h) caused a dose dependent suppression of the surge. A single dose of the GABAB receptor agonist baclofen (1 μg; icv) injected at 0855 h postponed the onset of the LH surge, and repeated injections at 0855 and 1130 h suppressed the surge. These data indicate that GABA-ergic activity in the brain can inhibit the LH surge in the cyclic rat via GABAA and GABAB receptors. Pro-oestrous rats were subjected to 5 hrs of restraint starting at 0855 h. Pretreatment with the GABAA receptor antagonist bicuculine (1 μg; icv) at 0840, 0940 and 1040 h or pretreatment with the GABAB receptor antagonist phaclofen (10 μg; icv) at 0840 h were ineffective in preventing the restraint-induced inhibition of the LH surge. The results suggest that GABAA and GABAB receptors are not involved in the inhibitory effect of restraint stress on the LH surge.     

Mild Traumatic Brain Injury in Sports: Neuropsychology's Contribution to a Developing Field

Mild traumatic brain injuries are common at all levels of athletic competition. Although once considered a routine part of the game, a significant amount of attention has recently been placed on these injuries at the professional, college, and high school levels. This paper reviews the epidemiology of sports-related brain injuries, the pathophysiology of the injuries, and the role of neuropsychology in this newly emerging area. Issues related to the adequacy of neuropsychological test instruments and approaches are discussed in light of future directions for research.     

Validity of the inventory of interpersonal problems for predicting treatment outcome: an investigation with the Pennsylvania Practice Research Network

In this study, we examined the relationship between treatment outcome and variables from the Inventory of Interpersonal Problems Circumplex scales (IIP-C; Horowitz, Alden, Wiggins, & Pincus, 2000) in the Pennsylvania Psychological Association's Practice Research Network (PRN; Borkovec, Echemendia, Ragusea, & Ruiz, 2001). The PRN was a naturalistic observation treatment outcome study conducted with clinicians who were providing outpatient therapy. Assessment instruments, including the Compass Assessment System (Howard, Brill, Lueger, O'Mahoney, & Grissom, 1993; Sperry, Brill, Howard, & Grissom, 1996) and the IIP-C, were used to assess outcome at the 7th session (N=73) and at termination (N=42). Significant associations were identified between seventh-session outcome and most of the IIP variables. Only IIP elevation and amplitude were related to termination outcome. Elevation, amplitude, and hostile submissive problems were related to treatment length. Ad hoc analyses indicated that the IIP elevation fully mediated the relationships between interpersonal problems and seventh-session outcome but not the relationship between amplitude and outcome. We discuss the results in relation to the external validity of the IIP.