Pelvic pain conditions are debilitating and treatment options are limited. A major issue contributing to this problem is the relative lack of understanding of factors underlying persistent visceral pain conditions – a much larger research effort exists in the area of somatic pain (e.g., pain of skin, skeletal muscle, bone origin).
The goal of this nGUDMAP molecular anatomy project is to map the primary structural and molecular features of a major population of nociceptor neurons that innervate the urinary bladder of the mouse. This project is relevant to genitourinary pain, such as interstitial cystitis/painful bladder syndrome. The experiments will focus on nociceptive neurons, identified in a Trpv1 reporter mouse, to develop a deeper understanding of their structure and connections with the bladder, and their ‘molecular fingerprint’ (RNA profile). The study will be performed on developing and mature mice, to capture the periods of time when major changes occur in bladder control.
In Aim 1, a topological map of Trpv1-positive axons within the embryonic and postnatal mouse bladder will be generated, enabling direct comparison with data on other neuronal populations available within GUDMAP. In Aim 2, deep sequencing techniques will be applied to characterize the transcriptome of particular populations of these Trpv1 neurons. First, specific dorsal root ganglia (DRG) will be dissected and Trpv1-positive and –negative neurons separated using fluorescence activated cell sorting (FACS). This will allow their total RNA to be sequenced and characterized, building a molecular map of the development and maturation of these nociceptors. By applying the latest bioinformatics analyses this will (i) identify transcripts unique to DRG that contain visceral nociceptors, and (ii) by micro-injecting retrograde tracing methods prior to tissue sampling, characterize the transcriptome of bladder-projecting nociceptive neurons. Together, this data will provide a rich source of knowledge to seed future hypothesis-driven studies on development and maturation of urogenital nociceptors, as well as potential application to studies on disease models.
Grant number: 1U01DK101029