LN-PMUT ultrasonic transducer enables instantaneous blood pressure reduction via renal hilar implantation.

Ma, Jun; Xing, Zhanqiang; Zhao, Yifei; Sun, Chenchen; Chen, Kexin; Ji, Weiliang; Hu, Teng; Wang, Junwen et al. · Biomaterials · 2026

basic_science · Level V

Where this comes from

Abstract

Blood pressure (BP) is a fundamental vital sign, yet no implantable device for BP modulation is currently available. Here, we present a miniaturized ultrasound probe based on lead-free lithium niobate (LN) piezoelectric micromachined ultrasonic transducer (PMUT) technology. The device features a dual-electrode design offering enhanced emission sensitivity and acoustic output, while maintaining a compact size (3 × 3 mm<sup>2</sup>, 3 mg), wide bandwidth (∼32%), and 2.5 MHz resonant frequency. Unilateral placement and vibratory stimulation at the renal hilum induced an immediate reduction in BP. Daily stimulation over one week reproducibly lowered BP, although the effect was limited to the stimulation period. Probe activation reduced renal vascular resistance and increased renal perfusion without observable structural damage or renal dysfunction within the study period. Transcriptomic sequencing of renal hilar tissue revealed bilateral nervous system changes following stimulation. Further analysis suggested that the hypotensive effect is partially mediated by sensory nerve release of calcitonin gene-related peptide (CGRP). Additionally, transcriptomic analysis revealed alterations in endocrine-related pathways on the stimulated side, particularly aldosterone-related pathways. In conclusion, renal hilar implantation of an LN-PMUT ultrasound probe achieves immediate BP reduction and may involve neural and endocrine pathway alterations associated with BP regulation, offering a potential strategy for the development of implantable BP regulators.