The role of pituitary adenylyl cyclase-activating polypeptide in the motivational effects of addictive drugs.

Pituitary adenylyl cyclase activating polypeptide (PACAP) was originally isolated from the hypothalamus and found to stimulate adenylyl cyclase in the pituitary. Later studies showed that this peptide and its receptors (PAC1, VPAC1, and VPAC2) are widely expressed in the central nervous system (CNS). Consistent with its distribution in the CNS, the PACAP/PAC1 receptor system is involved in several physiological responses, such as mediation of the stress response, modulation of nociception, regulation of prolactin release, food intake, etc. This system is also implicated in different pathological states, e.g., affective component of nociceptive processing, anxiety, depression, schizophrenia, and post-traumatic stress disorders. A review of the literature on PubMed revealed that PACAP and its receptors also play a significant role in the actions of addictive drugs. The goal of this review is to discuss the literature regarding the involvements of PACAP and its receptors in the motivational effects of addictive drugs. We particularly focus on the role of this peptide in the motivational effects of morphine, alcohol, nicotine, amphetamine, methamphetamine, and cocaine. This article is part of the special issue on Neuropeptides.

Factors influencing outcome in patients with colloid cysts who present with acute neurological deterioration.

Colloid cysts have been associated with acute neurologic deterioration and sudden death. However, the low incidence of associated sudden deaths has meant that factors influencing outcome in patients who present with acute neurological deterioration have not been extensively published. A PubMed literature search was performed to identify reported patients who presented with acute neurological deterioration with radiographic or histopathologic diagnosis of a colloid cyst. Demographic data, presenting symptoms, physical exam, surgical interventions, and outcomes were recorded. Analysis included 140 patients. Mean cyst size was 2.12 cm in males and 1.59 cm in females (p = 0.155), and 1.64 cm in patients who survived and 2.05 cm in patients who died (p = 0.04). Minimum cyst size was 0.4 cm in females and 0.8 cm in males. All patients without surgical intervention died, versus 48% with surgical intervention (p < 0.0001). Patient age was not significantly associated with outcome. Patients with hydrocephalus who have symptomatic colloid cysts are at extremely high risk for acute neurological deterioration and sudden death. Larger cyst size was associated with higher mortality, regardless of intervention. Prompt surgical intervention in extremis can lead to survival in approximately half the patients. Females, even with smaller cyst sizes, may be more likely to die before any intervention and may therefore benefit from more aggressive treatment approaches.

Endoscopic Endonasal Versus Microscopic Transsphenoidal Surgery for Recurrent and/or Residual Pituitary Adenomas.

OBJECTIVE: Surgery for recurrent/residual pituitary adenomas is increasingly being performed through endoscopic surgery. Whether this new technology has altered the indications and outcomes of surgery is unknown. We conducted a systematic review and meta-analysis of published studies to compare the indications and outcomes between microscopic and endoscopic approaches. METHODS: A PubMed search was conducted (1985-2015) to identify surgical series of endoscopic endonasal and microscopic transsphenoidal resection of residual or recurrent pituitary adenomas. Data were extracted regarding tumor characteristics, surgical treatment, extent of resection, endocrine remission, visual outcome, and complications. RESULTS: Twenty-one studies met inclusion criteria. A total of 292 patients were in the endoscopic group, and 648 patients were in the microscopic group. Endoscopic cases were more likely nonfunctional (P < 0.001) macroadenomas (P < 0.001) with higher rates of cavernous sinus invasion (P = 0.012). The pooled rate of gross total tumor resection was 53.5% for the endoscopic group and 46.6% for the microscopic group. Endocrine remission was achieved in 53.0% and 46.7% of patients, and visual improvement occurred in 73.2% and 49.6% for the endoscopic and microscopic groups. Cerebrospinal fluid leak and pituitary insufficiency were higher in the endoscopic group. CONCLUSION: This meta-analysis indicates that the use of the endoscope to reoperate on residual or recurrent adenomas has only led to modest increases in resection rates. However, larger more complex cases are being tackled, so direct comparisons are misleading. The most dramatic change has been in visual improvement along with modest increases in risk. Reoperation for recurrent or residual adenomas is a safe and effective treatment option.