Classically associated with control of membrane potential in excitable cells, the calcium-activated large conductance potassium channel (MaxiK, otherwise known as BK) has more recently been identified in cells of connective tissues, namely chondrocytes [1] and osteoblasts [2]. However, no studies have identified the expression of this channel, or indeed any other ion channel, in the human intervertebral disc (IVD) which contains chondrocyte-like cells. Our aim is to identify the expression of ion channels in the IVD. To date we have used reverse transcription polymerase chain reaction (RT-PCR) to examine the expression of MaxiK channels in normal and degenerate IVDs. Fourteen human IVD samples were chosen for analysis. These included 4 non-degenerate (mean age 51 years) and 10 degenerate (mean age 43 years) discs. Tissues were analysed for features of degeneration and separated into nucleus pulposus (NP) and annulus fibrosis (AF) tissue, and cells and RNA directly extracted. RT-PCR was conducted using primers for the alpha subunit of the MaxiK channel. GAPDH was used as a housekeeping gene and normal articular chondrocyte and the neuroblastoma cell line SH-SY5Y as positive controls. RT-PCR confirmed MaxiK channel expression in the degenerate IVD, both in the AF and NP. However, no expression of the channel was observed in the normal tissue, irrespective of disc region. We have shown for the first time that human IVDs express MaxiK channels and that the level of expression is not dependent on disc region or patient age. In addition we have demonstrated that these channels are not expressed in normal disc, but are only present in the degenerate IVD. These findings have implications for understanding the phenotype of cells within the normal and degenerate IVD. Furthermore it is hoped that as we expand the repertoire of ion channel markers it will help elucidate the pathophysiology of IVD degeneration.