Evaluation of Patient Reported Safety and Efficacy of Cannabis From a Survey of Medical Cannabis Patients in Canada.

With the medical use of cannabis permitted in Canada since 2001, patients seek to use this botanical drug to treat a range of medical conditions. However, many healthcare practitioners express the need for further scientific evidence around the use of medical cannabis. This real-world evidence study aimed to address the paucity of scientific data by surveying newly registered medical cannabis patients, before beginning medical cannabis treatment, and at one follow up 6 weeks after beginning medical cannabis treatment.

Adult-Born Hippocampal Neurons Undergo Extended Development and Are Morphologically Distinct from Neonatally-Born Neurons.

During immature stages, adult-born neurons pass through critical periods for survival and plasticity. It is generally assumed that by 2 months of age adult-born neurons are mature and equivalent to the broader neuronal population, raising questions of how they might contribute to hippocampal function in old age when neurogenesis has declined. However, few have examined adult-born neurons beyond the critical period or directly compared them to neurons born in infancy.

Human Pharmacokinetic Parameters of Orally Administered Δ-Tetrahydrocannabinol Capsules Are Altered by Fed Versus Fasted Conditions and Sex Differences.

There is variability in the reported Δ-tetrahydrocannabinol (THC) and 11-hydroxy-tetrahydrocannabinol (11-OH-THC) pharmacokinetic (PK) and pharmacodynamic (PD) parameters between studies and there is limited investigation into how the presence of food or sex affect these parameters. In this study, we examined the PK and PD parameters of an encapsulated THC extract and its major active metabolite, 11-OH-THC, under different fed states. The study was a single-dose, randomized, double-blinded, four-way crossover investigation.

Dentate gyrus neurons that are born at the peak of development, but not before or after, die in adulthood.

Introduction: In the dentate gyrus of the rodent hippocampus, neurogenesis begins prenatally and continues to the end of life. Adult-born neurons often die in the first few weeks after mitosis, but those that survive to 1 month persist indefinitely. In contrast, neurons born at the peak of development are initially stable but can die later in adulthood.

A combination of running and memantine increases neurogenesis and reduces activation of developmentally-born dentate granule neurons in rats.

During hippocampal-dependent memory formation, sensory signals from the neocortex converge in the dentate gyrus. It is generally believed that the dentate gyrus decorrelates inputs in order to minimize interference between codes for similar experiences, often referred to as pattern separation. The proportion of dentate neurons that are activated by experience is therefore likely to impact how memories are stored and separated.

Differential Effects of Extended Exercise and Memantine Treatment on Adult Neurogenesis in Male and Female Rats.

Adult neurogenesis has potential to ameliorate a number of disorders that negatively impact the hippocampus, including age-related cognitive decline, depression, and schizophrenia. A number of treatments enhance adult neurogenesis including exercise, NMDA receptor antagonism, antidepressant drugs and environmental enrichment. Despite the chronic nature of many disorders, most animal studies have only examined the efficacy of neurogenic treatments over short timescales (≤1 month).

Early survival and delayed death of developmentally-born dentate gyrus neurons.

The storage and persistence of memories depends on plasticity in the hippocampus. Adult neurogenesis produces new neurons that mature through critical periods for plasticity and cellular survival, which determine their contributions to learning and memory. However, most granule neurons are generated prior to adulthood; the maturational timecourse of these neurons is poorly understood compared to adult-born neurons but is essential to identify how the dentate gyrus (DG), as a whole, contributes to behavior.

Running promotes spatial bias independently of adult neurogenesis.

Different memory systems offer distinct advantages to navigational behavior. The hippocampus forms complex associations between environmental stimuli, enabling flexible navigation through space. In contrast, the dorsal striatum associates discrete cues and favorable behavioral responses, enabling habit-like, automated navigation.

Mice use start point orientation to solve spatial problems in a water T-maze.

Behavioral work has demonstrated that rats solve many spatial problems using a conditional strategy based on orientation at the start point. The present study assessed whether mice use a similar strategy and whether the strategy would be affected by the poorer directional sensitivity of mice. In Experiment 1, mice were trained on a response, a direction or one of two place problems to locate a hidden platform in a water T-maze located in two positions.

An examination of early neural and cognitive alterations in hippocampal-spatial function of ghrelin receptor-deficient rats.

Ghrelin, a hormone implicated in the regulation of feeding and energy balance, has also been associated with neural function underlying learning and memory. These effects are thought to be mediated by ghrelin targeting receptors at extra hypothalamic sites such as the hippocampus. Exogenous ghrelin administration increases dendritic spine density in the hippocampal CA1 region and neurogenesis in the dentate gyrus (DG), while improving memory in rats.