Cervix Stimulation Evokes Predominantly Subthreshold Synaptic Responses in Mouse Thoracolumbar and Lumbosacral Superficial Dorsal Horn Neurons

IntroductionSensory input from the female reproductive tract (FRT) plays a pivotal role in coordinating reproductive reflexes. Additionally, a number of disorders, especially chronic pelvic pain, may be due to disturbances in sensory processing of signals from the FRT.AimsOur aim was to record synaptic responses in neurons from lumbar and sacral spinal cord segments during mechanical stimulation of the cervix.MethodsWe developed an in vivo preparation of the mouse spinal cord to record synaptic potentials from superficial dorsal horn (SDH) neurons under whole-cell patch clamp recording conditions.Main Outcome MeasuresWe analyzed the strength and distribution of excitatory postsynaptic potentials in SDH neurons evoked during mechanical stimulation of the cervix and cutaneous sites.ResultsResting membrane potential and neuronal input resistance was similar in thoracolumbar (TL, T13-L3) and lumbosacral (LS, L6-S2) segments. We elicited activity in 6/21 TL neurons and 15/39 LS neurons using mechanical stimulation of the cervix with a blunt probe. The majority of these neurons responded to cervix stimulation with bursts of subthreshold excitatory postsynaptic potentials (4/6 and 12/15 TL and LS neurons, respectively). The remainder responded with sufficient magnitude to generate action potentials (2/6 and 3/15 TL and LS neurons). Cutaneous synaptic inputs were also elicited in 11/21 TL neurons following stimulation of the flank/leg, 19/39 LS neurons by stimulation of the tail, and three LS neurons by perineal stimulation. Some neurons received convergent synaptic inputs from the cervix and cutaneous sites (4/6 TL and 4/15 LS).ConclusionThese data demonstrate that spinal projections of cervix afferents are widely dispersed in the SDH and considerable convergence exists between neurons innervating the cervix and cutaneous structures. Our results indicate that much of the synaptic activity evoked in SDH neurons following cervix stimulation is subthreshold. Jobling P, Graham BA, Brichta AM, and Callister RJ. Cervix stimulation evokes predominantly subthreshold synaptic responses in mouse thoracolumbar and lumbosacral superficial dorsal horn neurons.     

The importance of depression and alcohol use in coronary artery bypass graft surgery patients: risk factors for delirium and poorer quality of life

Objective To investigate whether depression, anxiety and stress increase the risk for delirium and poor quality of life (QOL) after coronary artery bypass (CABG) surgery. Methods A total of 180 CABG patients (mean age of 63.5 ± 10.1 years, 82.2% males) completed baseline and postoperative self-report questionnaires to assess distress and QOL. Incident delirium was diagnosed postoperatively with a structured clinical interview and patients were monitored every day post-operatively for confusion and disturbance in consciousness. Results Delirium developed in 63 persons (35% of sample). After adjustment for covariates, delirium was significantly associated with depression [odds ratio (OR): 1.08; 95% confidence interval (CI): 1.03–1.13, P = 0.003], anxiety (OR: 1.07; 95% CI: 1.02–1.13, P = 0.01) and stress (OR: 1.05; 95% CI: 1.00–1.09, P = 0.03). Preoperative depression scores were associated with poorer QOL including bodily pain (β = -0.39, P = 0.013), vitality (β=-0.32, P = 0.020), social functioning (β = -0.51, P ≤ 0.001), emotional role function (β = -0.44, P = 0.003) and general health (β = -0.33, P = 0.038). Among the covariates, harmful levels of alcohol use was consistently associated with poorer QOL. Conclusions Depression and harmful levels of alcohol use were consistently associated with poorer QOL whereas depression, anxiety and stress were associated with delirium risk. These findings point to further research examining depression and harmful levels of alcohol use in coronary heart disease populations undergoing coronary revascularization.