GABAergic signaling from amacrine cells (ACs) is a fundamental aspect of visual signal processing in the inner retina. We have previously shown that nitric oxide (NO) can elicit release of GABA independently from activation of voltage-gated Ca channels in cultured retinal ACs. This voltage-independent quantal GABA release relies on a Ca influx mechanism with pharmacological characteristics consistent with the involvement of the transient receptor potential canonical (TRPC) channels TRPC4 and/or TRPC5. To determine the identity of these channels, we evaluated the ability of NO to elevate dendritic Ca and to stimulate GABA release from cultured ACs under conditions known to alter the function of TRPC4 and 5. We found that these effects of NO are phospholipase C dependent, have a biphasic dependence on La, and are unaffected by moderate concentrations of the TRPC4-selective antagonist ML204. Together, these results suggest that NO promotes GABA release by activating TRPC5 channels in AC dendrites. To confirm a role for TRPC5, we knocked down the expression of TRPC5 using CRISPR/Cas9-mediated gene knockdown and found that both the NO-dependent Ca elevations and increase in GABA release are dependent on the expression of TRPC5. These results demonstrate a novel NO-dependent mechanism for regulating neurotransmitter output from retinal ACs. NEW & NOTEWORTHY Elucidating the mechanisms regulating GABAergic synaptic transmission in the inner retina is key to understanding the flexibility of retinal ganglion cell output. Here, we demonstrate that nitric oxide (NO) can activate a transient receptor potential canonical 5 (TRPC5)-mediated Ca influx, which is sufficient to drive vesicular GABA release from retinal amacrine cells. This NO-dependent mechanism can bypass the need for depolarization and may have an important role in processing the visual signal by enhancing retinal amacrine cell GABAergic inhibitory output.

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Methods: A survey was developed and sent to patients participating in a pediatric teleurology program at an academic medical center. This survey evaluated the patient’s history using this telemedicine platform, satisfaction with various aspects of the application as well as associated details about transportation and costs of traditional in-person visits. Results: Of the 50 survey respondents, the majority reported that they found the app easy and comfortable to use as well as just as useful as in-person visits. Respondents also indicated that they incurred lower costs, traveled less, and faced less time lost from work. Conclusions: Telemedicine is a useful tool to enhance low-acuity pediatric urology care while minimizing the financial and opportunity costs of these visits as compared to in-person visits.

We assessed the same-day availability of oral emergency contraception (EC) in five Louisiana communities, and evaluated this data for relationships between availability and local population demographics. Researchers called all retail pharmacies in five municipalities of varying sizes in order to inquire about the same-day stockage of EC products and their availability to teens. Individual pharmacies were then geolocated to a census tract, and call data was analyzed against neighborhood census data regarding population size, income, gender, race, family structure, and educational level. A multivariable logistic regression model was performed to predict the same-day availability of emergency contraception. EC was available on the same day in 66% of all pharmacies. The same-day availability of EC decreased with the local population size (p < 0.001), and the availability increased with higher levels of educational attainment (p = 0.0015). The largest census level predictor of access to same-day EC was the city population, with the availability increasing by 6.6% for every 10,000 person increase in population. Despite changing to over-the-counter sales in 2013, EC is still not widely available in all geographic areas. Its availability is partially predictable by local population demographics, and this difference may represent a health disparity for teens and women seeking EC.

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